Keaguard: enable translucent keyguard by default

currently it is possible to enable it per device over an overlay and it is disabled
by default. Enable it by default but respect general transluscent disable from
device tree. Manta eg disables this feature due of graphical glichtes.

Change-Id: I3579d47ee3bee05719ef357ffcf19c0137b2302f
fb: add back notification shortcuts feature + common slim classes

beside our unique slim feature this patch adds

- all system shortcut icons we need for this and other stuff in future
- basice slim helper and constants classes we need later as well
- device utils helper
- preparation for navbar navring and other shortcut features
- and of course our notification shortcuts feature

compared to 4.3 some fixes were added + adapting to 4.4

xxhdpi icons thanks to kroz again

Change-Id: Ie552480007bde649352c699c8ff9ac10e79ed069