data usage cycle length

you can choose between daily, weekly or monthly data usage cycle

Change-Id: Idfbd9685541b14a36b8e99da5ea184ffb1c330fa
make LinearColorBar themeable

Move colors to resources and use them instead.

Change-Id: I923e5daa219f302dc24e62faab666483109e6620
Signed-off-by: Dirk Rettschlag <dirk.rettschlag@gmail.com>