DeskClock : Lockscreen dismiss Fix

https://jira.cyanogenmod.org/browse/CYAN-1116

Issue : Alarm dialog would unlock the lockscreen.
Resolution : Remove FLAG_DISMISS_KEYGUARD flag.

Change-Id: I9920376a2f8195b80f2907052dbfe353c4cb54a7
DeskClock: Add support for XXHDPI devices (e.g. Galaxy S4 and HTC One)

Change-Id: I9310e9067525da025d15a797f43c1b8cbc082272
DeskClock: Recreate alarms DB on downgrade

This fixed the cm10 to cm10.1 transition (from version 7 to 6)

Change-Id: Ia30915e8c4ebc36b191b5a876acbc8cb779b6689
JIRA: CYAN-1188
Issue: https://jira.cyanogenmod.org/browse/CYAN-1188
Signed-off-by: Jorge Ruesga <jorge@ruesga.com>