[Balloon] More LCD information

To help me mock up user interfaces on the Balloon, I've written a little
program called fbconvert which knows how to convert raw images into a
format suitable to copy into the Balloon's framebuffer. It should work
for mono and colour LCDs, and is described at:
http://www.balloonboard.org/wiki/index.php/LCDTesting

I hope this is useful to someone,
Chris