Merge branches 'NRLeuenb' and 'master' of https://github.com/nrleuenb/develop.bhs.m-g into NRLeuenb
Added the layout and the activity for the start screen. It now takes you to the games screen (which has a test image) and the group screen, which has the default hello world.

--NRLeuenb
Merge remote-tracking branch 'origin/master' into NRLeuenb