evita: commonize several overlay options

- move to common:
   config_defaultNotificationColor
   config_defaultNotificationLedOn
   config_defaultNotificationLedOff
   config_autoBrightnessLevels
   config_autoBrightnessLcdBacklightValues
   config_autoBrightnessButtonBacklightValues
   config_autoBrightnessKeyboardBacklightValues

- config_screenBrightnessDim already defaults to 10

Change-Id: I38f40b035e858907901ac2a4181413a0255e6d22