[WIP]Allow change of shared uid certificates by system apps

Makes it possible to flash from a Nexus/GPE factory image to a
custom ROM while retaining all data.

Due to some differences, these commands need to be run after
first boot into the new ROM followed by a reboot in order for
the home key and notification shade to work:

sqlite3 /data/data/com.android.providers.settings/databases/settings.db "update secure set value=1 WHERE name='user_setup_complete';"
sqlite3 /data/data/com.android.providers.settings/databases/settings.db "update global set value=1 WHERE name='device_provisioned';"

Change-Id: I3de4c8c6fd58cc8965f878dfb3a49269b2b22499
Revert "WIP-Add center clock. [1/2]"

This reverts commit 471a5aa0d5002ffd963b860468badb4304c44fe5.