FlightGear - Flight Simulator FGAddon

improvements on emis-animation on panel and surrounding surfaces
* switch _all_ emis factors to zero, if PanelLightsSwitch is off
* Let controls/lighting/instrument-lights-norm only vary between 0.1
and 1 (zero only when PanelLightsSwitch is off!) This gets rid of
awkward black holes, when panel is fully lit and instrument-lights
are off.
* simulate ambient light by emis on flightdecks unlit objects
(Rembrandt and non-Rembrandt rendering)