Disable debug line -- makes lot of noise in the unit tests.
Fix backwards running of RGB matrices
Fix some crashes in 2D view of fixture monitor

- when heads do not fully fill the fixture area
- when there is no FixtureMode (generic dimmers)
Removed data2valid vars in MidiPlugin

Removed the old and un-used data2valid vars called in midiprotocol. This
cleans up the code a bit.
Suggested by Jano.