add center clock.
delete unused sounds.
add multi-user support.
Revert "add multi-user support."

This reverts commit e9d7e9c01092afccd32651390f7b3fadbb96beb7.
add multi-user support.
more stable style.
Merge branch 'cm-10.1' of https://github.com/TheTEAMDev/android_frameworks_base into cm-10.1