Re-write code to match new pinouts for custom PCB.

Everything should be changed as needed, however this has not yet been tested.
Fix problem with spurious Timer2B interrupt causing hangs.

(Or at least work-around the problem, I am still not sure why I get
the spurious interrupt in the first place, but detecting and ignoring
it makes things work).

Also throw in a couple of minor fixes.
Some few fixes for the Mivi board for POV control.

Mostly it is using 10MHz instead of 20MHz for reading back the
dot-correction values from the TLC5940's. For some reason this fails
at 20MHz sometimes; it appears to be a software-problem, but hard to
track down, and we do not need speed for checking dot-correction
values anyway.
Fix bug where things would hang in SINGLE_BLADE mode, due to missing
initialisation of the SSI channels for the disabled blades.
Changes for running on the new robust mount.

Mainly implementing all three Hall sensors (as the available Hall
sensor happened to sit on wing two), selectable by #ifdef.
Adjust dot-correction values for LEDs to compensate for the dimmer perceived
brightness of the outer LEDs that need to swipe a larger area.
(Mostly) fix the frequent glitches in the picture stability.

Seems the hall sensor was getting stray signals from the motor coils or the
cable supplying current to the motor.

Attempt to filter that out by ignoring periods that seem to be too far off
what we expect.

I still saw a couple of glitches shortly after start, so might need some
fine-tuning, but it seems to help a lot, at least.
Adjust colour contrast, _much_ better now.

Space apart the higher colour numbers more, and the lower less, to
make the perceived difference between adjacent colour numbers 0-15
more equal. This greatly improves the contrast of eg. the displayed
cartoons.

Also adjust the angle to make the picture orientation correct and
attempt to tune the de-glitch values.

There is still an occasional glitch, but it's surely much improved
now, especially with the contrast fix.
Fix bug in frame receive that caused strange out-of-order frame rendering.

This would cause display glitches when the displayed image was
changing rapidly.
Modify lm4f_pov to be flashed over wireless.

This uses the bootloader from wireless_bootloader.c; the bootloader
occupies the lower 4 kB of flash, and the main lm4f_pov app now loads
at 0x1000.
Adjust angle between wings according to measurements.

Not 100% sure it matters much, but does seem to make the picture a bit
more stable.
Sync the TLC latching interrupt to the hall signal to improve picture stability.

In general, the rotation period will not be an integer multiple of the
PWM/latching period. But we want each pixel to ideally turn on and off at the
same spatial position in each refresh.

So implement synchonisation to achieve this (assuming stable rotation and hall
signal). When we get a hall signal, adjust the coming latching interrupt
period to make latching trigger at an integer number of PWM periods after the
time of the hall signal.

Also tweak the hall de-glitch parameters a bit, seems to help but more testing
will be needed to know for sure.