Updating all pxt.microbit.org reference to makecode.microbit.org (#460)

docs/device/serial.md

@@ -29,7 +29,7 @@ Unfortunately, using the serial library requires quite a bit of a setup.
 If you are using the Google Chrome browser, you can use our extension to get serial data streaming in the editor.
 
 * Install the [Extension for BBC micro:bit](https://chrome.google.com/webstore/detail/extension-for-bbc-microbi/cihhkhnngbjlhahcfmhekmbnnjcjdbge?hl=en-US) on the Chrome Web Store.
-* Restart Chrome and open the [web editor](https://pxt.microbit.org)
+* Restart Chrome and open the [web editor](@homeurl@)
 * The serial data will show below the simulator
 
 If the extension is enabled, it will not be possible to access the port/device for the micro:bit from other programs than Chrome.

docs/device/usb/mac-chrome.md

@@ -34,7 +34,7 @@ it appears as a new drive under Devices.
 
 ## Step 2: Download your program
 
-1. Open your project on [pxt.microbit.org](https://pxt.microbit.org)
+1. Open your project on @homeurl@
 2. Click **Download**
 3. When prompted, choose to **save** the compiled file onto your computer. The
    prompt will be different depending on which browser you are using, or

docs/device/usb/mac-firefox.md

@@ -34,7 +34,7 @@ it appears as a new drive under Devices.
 
 ## Step 2: Download your program
 
-1. Open your project on [pxt.microbit.org](https://pxt.microbit.org)
+1. Open your project on @homeurl@
 2. Click **Download**
 3. When prompted, choose to **save** the compiled file onto your computer. The
    prompt will be different depending on which browser you are using, or

docs/device/usb/mac-safari.md

@@ -34,7 +34,7 @@ it appears as a new drive under Devices.
 
 ## Step 2: Download your program
 
-1. Open your project on [pxt.microbit.org](https://pxt.microbit.org)
+1. Open your project on @homeurl@
 2. Click **Download**
 3. When prompted, choose to **save** the compiled file onto your computer. The
    prompt will be different depending on which browser you are using, or

docs/device/usb/windows-chrome.md

@@ -43,7 +43,7 @@ You only need to do this once.
 
 ## Step 3: Download your program
 
-1. Open your project on [pxt.microbit.org](https://pxt.microbit.org)
+1. Open your project on @homeurl@
 2. Click **Download**
 3. If you did Step 2 above, Chrome will ask where to save the `.hex` file,
     so save it into the `MICROBIT` drive.

docs/device/usb/windows-edge.md

@@ -36,7 +36,7 @@ it appears as a new drive under Devices.
 
 ## Step 2: Download your program
 
-1. Open your project on [pxt.microbit.org](https://pxt.microbit.org)
+1. Open your project on @homeurl@
 2. Click **Download**
 3. When prompted, choose to **save** the compiled file onto your computer. The
    prompt will be different depending on which browser you are using, or

docs/device/usb/windows-firefox.md

@@ -36,7 +36,7 @@ it appears as a new drive under Devices.
 
 ## Step 2: Download your program
 
-1. Open your project on [pxt.microbit.org](https://pxt.microbit.org)
+1. Open your project on @homeurl@
 2. Click **Download**
 3. When prompted, choose to **save** the compiled file onto your computer. The
    prompt will be different depending on which browser you are using, or

docs/device/usb/windows-ie.md

@@ -35,7 +35,7 @@ it appears as a new drive under Devices.
 
 ## Step 2: Download your program
 
-1. Open your project on [pxt.microbit.org](https://pxt.microbit.org)
+1. Open your project on @homeurl@
 2. Click **Download**
 3. When prompted, choose to **save** the compiled file onto your computer. The
    prompt will be different depending on which browser you are using, or