Fix mis-labled HGR_RED -> HGR_ORANGE
DOC: Made note that IIGS color reference is NOT accurate
Fix mis-labeled HGR_MAGENTA -> HGR_VIOLET
Removed old commented out color maps for Lores & DoubleHires
Fixed HGR colors to be more accurate; cleanup dead code; merged COLORS_TWEAKED since it is always active
Remove unused: V_CreateLookup_HiresHalfShiftFull(), conditionaly compile V_CreateLookup_HiresHalfShiftDim();