* Track status pin use by user code separately so it can take over the pins and then give them back.
* Switch to hardware SPI for APA102 on Gemma and Trinket.
* Merge microcontroller/types.h into microcontroller/Pin.h to better match approach going forwards.
The new sequence is as follows:
* Solid blue during the boot/settings script.
* Solid green during the main/code script.
* After main while waiting to enter repl or reset:
* Fading green once main is done successfully.
* On error produce a series of flashes:
* Long flash color of script.
* Long flash color of error:
* Green = IndentationError
* Cyan = SyntaxError
* White = NameError
* Orange = OSError
* Yellow = Other error
* Line number of the exception by digit. Number of flashes represents value.
* Thousands = White
* Hundreds = Blue
* Tens = Yellow
* Ones = Cyan
* Off for a period and then repeats.
At any point a write to the flash storage will flicker red.
Fixes#63
