[2/2] OmniGears: allow disabling haptic feedback for virtual keys

Allows disabling haptic feedback for devices with
capacitive buttons (virtual keys)

Change-Id: I8a4ceac650e611f8a110b08c9e9f7f074e4b22c4

Conflicts:
	res/values/custom_strings.xml
	res/xml/button_settings.xml
	src/org/omnirom/omnigears/ButtonSettings.java