Update Dotcase to support 24-hour time

Displays 12- or 24-hour time per standard system setting

Change-Id: I387e12a299fb4eb52d69d402be18d70947c9a5aa
Dotcase: Fix brightness sticking

The UEventObserver sees the case open, so it turns on the screen and
kills the Dotcase activity. But, then the BroadcastReceiver sees the
screen turn on, so it tries to launch the Dotcase "stuff," including
setting the brightness to max. Sometimes, the order in which these
things happen causes the brightness to get set to max after the
activity is killed, and it gets stuck there until the case is closed
and opened again.

Make the switchState a class variable and, in the BroadcastReceiver,
check whether the case is open before starting any of the Dotcase
stuff.

Change-Id: I08b40bff766d8af6e467bf5be36f770566cee31f
Dotcase: don't animate activity appearing

Change-Id: Id0696f93978c74078e6ab0f98bbbc2b0232fbff1
Dotcase: Define static colors to prevent reuse glitches

Change-Id: I9e4eb3e51df537d32e06cfcbb9d538caefe51b06
Dotcase: Improve exception-handling

Don't catch generic Exception, and log exceptions as errors. Also,
remove try-catch blocks around things which seemingly do not throw any
exception.

Change-Id: I333be1f178fec12f38caded0c176c93f6ed710b1
Dotcase: Only check for new notifications before displaying them

Rather than check for new notifications on every redraw, only check at
the beginning of each animation cycle (i.e., right before they're
about to be shown). This reduces notification checks from about twice
per second to about every 3 seconds.

Change-Id: Ia53de5bc24f3e41d33bfe5bc7c0f56b284e4d3e8