ILI9340 TFT display driver WIP; initialization code.

Largely ported from Adafruit's arduino/teensy driver.
On boot, write blue to ILI9340 TFT forever (very very slowly).

At 1 MHz it takes about a minute or two to fill the screen!
Makefile: separate writerom and verifyrom tasks.
ili9340: set screen to 200x200 with unused margins; loop fixed.