framework: Battery bar (1/2)

* Patch inspired by MIUI and originally ported by David Morgan / @Spitemare
* as a extra feature for custom @CyanogenMod 7 ROMs.  Patch has been adapted
* to work better on @SaberMod.  Much of the work was done by Daniel Nilsson / @syaoran12
* Patch is nearly identical in nature to how Dan has writen it, with a few
* minor changes in removing the option to have centered bar, which doesn't
* seem to work very well on some devices like the Nexus 7 (grouper).  Also
* does not check for devices with no navigation bar as @SaberMod only supports
* nexus devices that all have navigation bars.

Signed-off-by: Paul Beeler <sparksco@gmail.com>
SystemUI: fix memory leaks

ContentObservers are being registered without being unregistered,
causing old objects not to be garbage collected. This causes memory
leak if the classes are destroyed and recreated throughout the
device's uptime.

SearchPanelView is recreated every time the screen is turned on.

Signed-off-by: Paul Beeler <sparksco@gmail.com>