v2.0.0-beta.3

Changelog:

• Added pin.set_touch_mode() method (#14).
• Updated the pin argument in audio/music/speech play function (#30).
• The speaker enable/disable methods have been moved from pin_speaker.enable()/disable(), to speaker.on()/off()
• Exceptions now show the line number on serial
• microphone.is_event() now check the current event instead of the last in the internal list
• Assembly decorator enabled
• Fixes issue building with debian-packaged Arm GCC (#5)
• Updated CODAL to v0.2.24
  • Fixes an issue with sequential PWM DMA writes that have a small delaybetween them, eg when driving Neopixels (#27).
  • Fixes issues with incorrect serial data on startup and when buffer overflows (#15, #35)
  • Fixes issue with 0-length i2c operations.