Instrument panel updates from David Megginson.

Instrument panel updates from David Megginson.

- the panel uses much, much less texture memory, and draws much
  faster, at least on my hardware

- there is a wet (magnetic) compass at the top of the panel

- the gyro compass shows true heading again, but don't get used to it:
  we're going to set it up to drift soon

- there are TO/FROM flags on NAV1 and NAV2 (but no GS flag yet)

- the ADF looks a little more realistic (if you can forgive the ugly
  needle)

- when the HUD is not open, the framerate is moved to the right side
  of the screen so that it won't be obscured by the mag compass