[2/2] Settings: Add time-context headers to the notification header

This commit adds image headers to the notification panel header,
based on the date/time. There are pictures for morning, afternoon
and night, as well as special events like Christmas and new
year's eve.
More will be coming, with eventually a way to use an external
(as in, Internet) provider for those pictures.
AOKP custom system animations (2/2)

ported fom here: http://gerrit.aokp.co/#/c/12305/

Thanks to Steve Spear

PS2: Clean tabs
PS3: Some string fixes