replace icons

back
refresh
add AboutLibraries
use native cards for lvas
use native cards for timetable
add menu to calendar cards
fix coloring of menu and title in timetable
add headers to grid
use native cards for grades
use native cards for exams
small cosmetic changes
fix search on map
change string
use native cards for menus
use native cards for studies
use native cards for öh news
use native cards for statistics
fix theme of login screen

copy AccountAuthenticatorActivity and inherit from ActionBarActivity
fix theming of settings

needs support v4 preferencefragment (from library)
update dependencies
remove cardslib