overlay: initial als range for buttons/keyboard

Signed-off-by: Michael Bestas <mikeioannina@gmail.com>

Change-Id: I64c72b236b3a1db48133b0dbce419c021ffa7b96
Add README

Signed-off-by: Michael Bestas <mikeioannina@gmail.com>

Change-Id: I3337e33659e527581a0016366144d71833313b49