tuna: add support for battery LED charging

Device has multi-color RGB LED, enable charging function
using existing custom lights library and frameworks overlay

JIRA: CYAN-596
JIRA URL: https://jira.cyanogenmod.org/browse/CYAN-596

Change-Id: Iac3d9c36b96cda281ca94263305ae3ecc192f3e9
Merge remote-tracking branch 'upstream/kitkat' into kitkat