support for is-gesture (#1873)

* support for is-gesture

* updated shims

* activate shake button

* refactor

* refactor shake button

docs/reference/input.md

@@ -13,6 +13,7 @@ input.onPinPressed(TouchPin.P0, () => {
     
 });
 input.buttonIsPressed(Button.A);
+input.isGesture(Gesture.Shake);
 input.compassHeading();
 input.pinIsPressed(TouchPin.P0);
 input.temperature();
@@ -27,4 +28,6 @@ input.setAccelerometerRange(AcceleratorRange.OneG);
 
 ## See also
 
-[onButtonPressed](/reference/input/on-button-pressed), [onGesture](/reference/input/on-gesture), [onPinPressed](/reference/input/on-pin-pressed), [buttonIsPressed](/reference/input/button-is-pressed), [compassHeading](/reference/input/compass-heading), [pinIsPressed](/reference/input/pin-is-pressed), [temperature](/reference/input/temperature), [acceleration](/reference/input/acceleration), [lightLevel](/reference/input/light-level), [rotation](/reference/input/rotation), [magneticForce](/reference/input/magnetic-force), [runningTime](/reference/input/running-time), [setAccelerometerRange](/reference/input/set-accelerometer-range), [calibrate-compass](/reference/input/calibrate-compass)
+[onButtonPressed](/reference/input/on-button-pressed), [onGesture](/reference/input/on-gesture), [onPinPressed](/reference/input/on-pin-pressed), [buttonIsPressed](/reference/input/button-is-pressed), 
+[is gesture](/reference/input/is-gesture),
+[compassHeading](/reference/input/compass-heading), [pinIsPressed](/reference/input/pin-is-pressed), [temperature](/reference/input/temperature), [acceleration](/reference/input/acceleration), [lightLevel](/reference/input/light-level), [rotation](/reference/input/rotation), [magneticForce](/reference/input/magnetic-force), [runningTime](/reference/input/running-time), [setAccelerometerRange](/reference/input/set-accelerometer-range), [calibrate-compass](/reference/input/calibrate-compass)

docs/reference/input/is-gesture.md

@@ -0,0 +1,28 @@
+# Is Gesture
+
+Tests if a gesture is currently detected.
+
+```sig
+input.isGesture(Gesture.Shake)
+```
+
+## Parameters
+
+* ``gesture`` means the way you hold or move the @boardname@. This can be `shake`, `logo up`, `logo down`, `screen up`, `screen down`, `tilt left`, `tilt right`, `free fall`, `3g`, or `6g`.
+
+## Example: random number
+
+This program shows a number from `2` to `9` when you shake the @boardname@.
+
+```blocks
+forever(function() {
+    if (input.isGesture(Gesture.Shake)) {
+        let x = Math.randomRange(2, 9)
+        basic.showNumber(x)
+    }
+})
+```
+
+## See Also
+
+[on gesture](/reference/input/on-gesture)

docs/reference/input/on-gesture.md

@@ -24,3 +24,6 @@ input.onGesture(Gesture.Shake,() => {
 })
 ```
 
+## See Also
+
+[is gesture](/reference/input/is-gesture)