Align MICROBIT_PIN_EVENT_ON_* with codal

Align print() semantics with previous versions

  - fix regression in semantics
  - all print() operation of unit length now leave the screen uncleared, even
    when a duration is provided.

Ensure consistent behaviour of MicroBitDisplay::print() operations

  - Simplify behaviour of print() and printAsync() methods.
  - print(char) print(ManagedString) and print(MicroBitImage) now all have same semantics:

    - If provided, the delay parameter is always respected. Screen is cleared after that time.

    - discrete print operations (character, string of length 1 and MicroBitImage) with no
      delay parameter are printed, and return immeditely. The screen is not cleared.

    - print (string of length > 1) with no delay parameter defaults to a delay
      of MICROBIT_DEFAULT_PRINT_SPEED milliseconds. The screen is cleared on
      completion.

Honour delay parameter in MicroBitDisplay::print(MicroBitImage)

  - Fix bug microsoft/pxt-microbit#2739

Use schedule() not fiber_sleep(0) in MicroBitSerial.cpp (Fix #461)

  - MicroBitSerial use wake_on_event for condition synchronisation.
  - By contract, a fiber doing this should subsequently call schedule()
    and no other blocking operation

Re-enumerate component ID values to align with CODAL

  - Update component ID values to align with those used in CODAL
  - Just enables some code cleanup within MakeCode.

Re-enumerate component ID values to align with CODAL

  - Update component ID values to align with those used in CODAL
  - Just enables some code cleanup within MakeCode.

Merge branch 'radio-changes' into pxtgc-radio

Add fiber_user_data to yotta mappings; fix some errors

Add fiber_user_data to yotta mappings; fix some errors