VEHICLE_ENVIRONMENT and VEHICLE_ENVIRONMENT_COMMAND 6.11.5 and 6.11.6

Martin Perlot, of SilverLeaf Electronics. proposes the following addition

Addition to VEHICLE_ENVIRONMENT_STATUS and VEHICLE_ENVIRONMENT_COMMAND
Byte 3, Bits -,
Name: Ambient Light Level
Data Type: uint8
Unit: Percent
Value Definition: 0 = Dark. 200 = Daylight Conditions. Typically used to determine appropriate backlight levels for screens and indicators. For Solar Intensity, see WEATHER_STATUS_2.

Justification: This addition simplifies the coordination of backlight levels in the various screens and indicators within the RV.