pxt-microbit Accessibility PR (#529)

* Accessibility changes

docs/reference/images/create-big-image.md

@@ -14,13 +14,13 @@ images.createBigImage(`
     `);
 ```
 
-### Parameters
+## Parameters
 
 * ``leds`` is a [string](/types/string) that says which LEDs
 on the screen should be on and which should be off.
 
 
-### Example: Flip-flopping arrow
+## Example: Flip-flopping arrow
 
 This program makes a big image with a picture of an arrow pointing up,
 and an arrow pointing down.  If you press button `A`, the program will
@@ -44,7 +44,7 @@ input.onButtonPressed(Button.B, () => {
 });
 ```
 
-### See also
+## See also
 
 [image](/reference/images/image),
 [create image](/reference/images/create-image),

docs/reference/images/create-image.md

@@ -13,12 +13,12 @@ images.createImage(`
 `)
 ```
 
-### Parameters
+## Parameters
 
 * ``leds`` is a [string](/types/string) that says which LEDs
 on the screen should be on and which should be off.
 
-### Example: Flip-flopping arrow
+## Example: Flip-flopping arrow
 
 If you press button `A`, this program will make a picture of an
 arrow and show it on the LED screen. If you press button `B`, the
@@ -45,7 +45,7 @@ input.onButtonPressed(Button.B, () => {
 });
 ```
 
-### See also
+## See also
 
 [image](/reference/images/image),
 [create big image](/reference/images/create-big-image),

docs/reference/images/image.md

@@ -2,11 +2,11 @@
 
 An image for the @boardname@ screen.
 
-### @parent blocks/language
+## @parent blocks/language
 
 An *Image* is a matrix of pixels to show on the [LED screen](/device/screen)
 
-### Block Editor: Show LEDs
+## Block Editor: Show LEDs
 
 To display an image:
 
@@ -22,7 +22,7 @@ basic.showLeds(`
     `)
 ```
 
-### Creating an image
+## Creating an image
 
 To create an image that you can later modify, see the [create image](/reference/images/create-image) function.
 
@@ -38,7 +38,7 @@ You should see code similar to this:
 
 ![](/static/mb/blocks/image-0.png)
 
-### Image functions
+## Image functions
 
 * [create image](/reference/images/create-image): create an image from a series of on/off LED states
 * [clear](/reference/basic/clear-screen): turn off all the pixels in an image
@@ -47,7 +47,7 @@ You should see code similar to this:
 * [show image](/reference/images/show-image): show an image on the screen
 * [scroll image](/reference/images/scroll-image): scroll an image on the screen
 
-### See also
+## See also
 
 [Show LEDs](/reference/basic/show-leds), [create image](/reference/images/create-image), [show image](/reference/images/show-image), [LED screen](/device/screen)
 

docs/reference/images/pixel.md

@@ -4,30 +4,30 @@ The pixel function.
 
 Get the state of a pixel in an [Image](/reference/images/image).
 
-### JavaScript
+## JavaScript
 
 ```sig
 export function pixel(_this: micro_bit.Image, x: number, y: number) : boolean
 ```
 
-### Parameters
+## Parameters
 
 * x - [Number](/types/number); the *x coordinate* or horizontal position of a pixel in an [image](/reference/images/image)
 * y - [Number](/types/number); the *y coordinate* or vertical position of a pixel in an [image](/reference/images/image)
 
-### x, y coordinates?
+## x, y coordinates?
 
 To figure out the ``x``, ``y`` coordinates, see [LED screen](/device/screen).
 
-### Returns
+## Returns
 
 * [Boolean](/blocks/logic/boolean) - `true` for on and `false` for off
 
-### Example
+## Example
 
 This example gets the state of pixel `0, 0` in the `img` variable:
 
-### ~hide
+## ~hide
 
 ```blocks
 let img = images.createImage(`
@@ -39,13 +39,13 @@ let img = images.createImage(`
 `)
 ```
 
-### ~
+## ~
 
 ```typescript-ignore
 let state = img.pixel(0, 0)
 ```
 
-### See also
+## See also
 
 [set pixel](/reference/images/set-pixel), [show image](/reference/images/show-image), [image](/reference/images/image), [create image](/reference/images/create-image), [scroll image](/reference/images/scroll-image)
 

docs/reference/images/plot-frame.md

@@ -4,21 +4,21 @@ The plot frame function.
 
 Display an [Image](/reference/images/image) on the @boardname@'s [LED screen](/device/screen)
 
-### JavaScript
+## JavaScript
 
 ```sig
 export function plotFrame(_this: micro_bit.Image, index: number)
 ```
 
-### Parameters
+## Parameters
 
 * index - [Number](/types/number); which frame of the image to display
 
-### Difference from `plot image`
+## Difference from `plot image`
 
 The `plot frame` function takes the index of the frame (if there are two frames, then the possible indices are 0 and 1), whereas `plot image` accepts an offset (if there are two frames, the offset would range between 0 and 9).
 
-### Example
+## Example
 
 ```blocks
 let img = images.createImage(`
@@ -31,7 +31,7 @@ let img = images.createImage(`
 img.plotFrame(1)
 ```
 
-### See also
+## See also
 
 [create image](/reference/images/create-image), [show animation](/reference/basic/show-animation), [image](/reference/images/image), [show image](/reference/images/show-image), [scroll image](/reference/images/scroll-image)
 

docs/reference/images/plot-image.md

@@ -4,21 +4,21 @@ The plot image function.
 
 Display an [Image](/reference/images/image) on the @boardname@'s [LED screen](/device/screen)
 
-### JavaScript
+## JavaScript
 
 ```sig
 export function plotImage(_this: micro_bit.Image, xOffset: number)
 ```
 
-### Parameters
+## Parameters
 
 * x offset - [Number](/types/number); the horizontal starting point of an image; use 0 for the first frame of the image, 5 for the second frame of the image, 10 for the third frame and so on.
 
-### Difference from `show image`
+## Difference from `show image`
 
 The `show image` function has a built in delay of 400ms after display of the image, whereas `plot image` has no built-in delay.
 
-### Example
+## Example
 
 ```blocks
 let img = images.createImage(`
@@ -31,7 +31,7 @@ let img = images.createImage(`
 img.plotImage(0)
 ```
 
-### See also
+## See also
 
 [create image](/reference/images/create-image), [show animation](/reference/basic/show-animation), [image](/reference/images/image), [show image](/reference/images/show-image), [scroll image](/reference/images/scroll-image)
 

docs/reference/images/scroll-image.md

@@ -8,7 +8,7 @@ let item: Image = null;
 item.scrollImage(5, 200);
 ```
 
-### Parameters
+## Parameters
 
 * a [number](/types/number) that means
   how many LEDs to scroll at a time, from right to left or
@@ -25,7 +25,7 @@ item.scrollImage(5, 200);
   ``offset`` says. (1000 milliseconds is one second.) The bigger you
   make this number, the slower the image will scroll.
 
-### Example
+## Example
 
 This program scrolls an image of two arrows five LEDs at a time,
 with a pause of 200 milliseconds between each time it scrolls.
@@ -47,7 +47,7 @@ basic.forever(() => {
 });	
 ```
 
-### See also
+## See also
 
 [show image](/reference/images/show-image), [image](/reference/images/image), [create image](/reference/images/create-image), [show animation](/reference/basic/show-animation)
 

docs/reference/images/set-pixel.md

@@ -4,23 +4,23 @@ The set pixel function. #set pixel.
 
 Set the on/off state of pixel in an [Image](/reference/images/image).
 
-### JavaScript
+## JavaScript
 
 ```sig
 export function setPixel(_this: micro_bit.Image, x: number, y: number, value: boolean)
 ```
 
-### Parameters
+## Parameters
 
 * x - [Number](/types/number); the *x coordinate* or horizontal position of a pixel in an [image](/reference/images/image)
 * x - [Number](/types/number); the *y coordinate* or vertical position of a pixel in an [image](/reference/images/image)
 * value -[Boolean](/blocks/logic/boolean); the on/off state of a pixel; `true` for on, `false` for off
 
-### x, y coordinates?
+## x, y coordinates?
 
 To figure out the ``x``, ``y`` coordinates, see [LED screen](/device/screen).
 
-### Example
+## Example
 
 The following example creates an image and stores it in the `img` variable. The `set pixel` function sets the centre pixel off, before `img` is shown using `show image`.
 
@@ -36,7 +36,7 @@ img.setPixel(2, 2, false)
 img.showImage(0)
 ```
 
-### See also
+## See also
 
 [pixel](/reference/images/pixel), [show image](/reference/images/show-image), [image](/reference/images/image), [create image](/reference/images/create-image), [scroll image](/reference/images/scroll-image)
 

docs/reference/images/show-frame.md

@@ -4,21 +4,21 @@ The show frame function.
 
 Display an [Image](/reference/images/image) on the @boardname@'s [LED screen](/device/screen)
 
-### JavaScript
+## JavaScript
 
 ```sig
 export function showFrame(img: micro_bit.Image, frame: number)
 ```
 
-### Parameters
+## Parameters
 
 * index - [Number](/types/number); which frame of the image to display
 
-### Difference from `plot frame`
+## Difference from `plot frame`
 
 The `show frame` function is the same as [plot frame](/reference/images/plot-frame), but contains a built-in delay after the LED screen has been updated (whereas `plot frame` has no built-in delay)
 
-### Example
+## Example
 
 ```blocks
 let img = images.createImage(`
@@ -31,7 +31,7 @@ let img = images.createImage(`
 img.showFrame(1)
 ```
 
-### See also
+## See also
 
 [create image](/reference/images/create-image), [show animation](/reference/basic/show-animation), [image](/reference/images/image), [show image](/reference/images/show-image), [scroll image](/reference/images/scroll-image)
 

docs/reference/images/show-image.md

@@ -9,12 +9,12 @@ let item: Image = null;
 item.showImage(0);
 ```
 
-### Parameters
+## Parameters
 
 * an [image](/reference/images/image) (picture). It is usually a square with five LEDs on a side, but it might be wider. 
 * a [number](/types/number) that says how many LEDs from the left of the picture the @boardname@ should start. `0` means start at the first **frame** of the picture, `5` means start at the second frame, `10` means start at the third, and so on.
 
-### Example: Flip-flopping arrow
+## Example: Flip-flopping arrow
 
 This program makes a big image with a frame of an arrow pointing up,
 and a frame of an arrow pointing down.  If you press button `A`, the
@@ -39,7 +39,7 @@ input.onButtonPressed(Button.B, () => {
 });
 ```
 
-### See also
+## See also
 
 [image](/reference/images/image),
 [create image](/reference/images/create-image),

docs/reference/images/width.md

@@ -8,17 +8,17 @@ Get the width of an [Image](/reference/images/image) in columns.
 images.createImage().width();
 ```
 
-### Parameters
+## Parameters
 
 * none
 
-### Returns
+## Returns
 
 * [Number](/types/number) - the number of columns in a image. This function returns 5 if the image has 1 frame, 10 for 2 frames, 15 for 3 frames and so on. Divide the number of columns by 5 to find out how many frames an image has (see example below).
 
 The following example gets the width of `img` and stores it in the `w` variable:
 
-### ~hide
+## ~hide
 
 ```blocks
 let img = images.createImage(`
@@ -30,13 +30,13 @@ let img = images.createImage(`
 `)
 ```
 
-### ~
+## ~
 
 ```typescript-ignore
 let w = img.width()
 ```
 
-### Example: show each frame
+## Example: show each frame
 
 The following example uses the `width` function with a [for](/blocks/loops/for) loop to show each image frame on the screen:
 
@@ -54,7 +54,7 @@ for (let i = 0; i < img2.width() / 5; i++) {
 }
 ```
 
-### See also
+## See also
 
 [show image](/reference/images/show-image), [image](/reference/images/image), [create image](/reference/images/create-image), [scroll image](/reference/images/scroll-image), [show animation](/reference/basic/show-animation)