Key forwarding and single app mode update

Added new Launcher activity to be used for Single App Mode (when
resuming, instructs client to exit video activity).
Added handler to determine which mode the client is using and
start the appropriate launcher and/or app.
Added SVMP_BROADCAST permission and updated broadcast receivers
appropriately.
Added Config handler to deal with hardware keyboard config
messages and interface with the InputManagerService.
Revamped Notification handler to deal with new 4.2.2 changes that
broke it.
Cleaned up unnecessary broadcasts and permissions.
Added various comments and logging updates.

Co-commits:
android_device_mitre_svmp
android_frameworks_base
svmp-android-client
svmp-protocol-def
svmp-server