feedback for topbar added
Merge remote-tracking branch 'origin/master' into 8.37P_feedback_for_topbar_buttons
Merge remote-tracking branch 'origin/master' into 8.37P_feedback_for_topbar_buttons
Tests: changed topbar buttons to imagebuttons
Merge pull request #38 from Catrobat/8.37P_feedback_for_topbar_buttons

feedback for topbar added
acceptance: @PeteSVS [PP]
implementation: @schmidiM [MS]