liblights: allow to turn keys off and on

Change-Id: I9fab70658c5fee2e9897c3b45f9c47ac81dc19e2
Merge remote-tracking branch 'nameless/android-4.4' into cm-11.0
Fix some leftover merge derpings for test build

Change-Id: Id2410a9081a5f3351068d696fd8c02efcc8e69cb