HUGE AVR RAM optimization (~28%).

- It's possible to get even more, but this is probably as far as I'll go
- PROGMEM is really annoying to use, and makes the code look like ass
- Now the Teensy 2++ should have enough RAM to use PartialMap easily
Adding timeout to virtual serial port writes

- Was causing lock-ups until the serial port was read
- Also checking each of the NKRO key types in each send loop