inserted new icons
Merge pull request #499 from Catrobat/logos

inserted new icons
CAT-497 #code-review fixes #497
fixed testcase for jenkins
Merge pull request #500 from Catrobat/issue#497

Option to create empty program
fixed some warnings plus version update
Merge pull request #501 from Catrobat/versionUpdate

fixed some warnings plus version update
Added a callback interface to StageListener.
Updated steps and definitions.
Merge branch 'master' into cucumber-test