Lockscreen customization

lockscreen targets
added magnetic targets: can slide to unlock anywhere on ring (stock jb42)
add option to minimize/maximize widgets on add to lockscreen
add option to show/hide widget tray hints

PS4: rebase
PS5: Hopefully fix invisiable font with inverted themes

Change-Id: Ib3e6eef6e4ce6051d18cbf205db0c6149a1709a0
Signed-off-by: DHO <DHO@dho.im>

Conflicts:

	AndroidManifest.xml
	res/drawable-mdpi/ic_empty.png
	res/layout/pick_item.xml
	res/values/arrays.xml
	res/xml/display_settings.xml