* 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.
This prevents corrupting previous functional objects by stealing their pins
out from under them. It prevents this by ensuring that pins are in default
state before claiming them. It also verifies pins are released correctly and
reset on soft reset.
Fixes#4, instantiating a second class will fail.
Fixes#29, pins are now reset too.