Calibrate compass (#392)

* adding 'calibrate-compass' function

* fixing simulator.

* updated docs

* fixing compat test suite with 'calibrate()' function

libs/core/shims.d.ts

@@ -339,8 +339,9 @@ declare namespace input {
     /**
      * Obsolete, compass calibration is automatic.
      */
-    //% help=input/calibrate weight=0 shim=input::calibrate
-    function calibrate(): void;
+    //% help=input/calibrate-compass advanced=true
+    //% blockId="input_compass_calibrate" block="calibrate compass" shim=input::calibrateCompass
+    function calibrateCompass(): void;
 
     /**
      * Sets the accelerometer sample range in gravities.