Merge pull request #75 from exside/master

Menu Ratings get sent to server now, webservice and other refactorings (read comment)
Merge pull request #78 from exside/master

Updates and refactoring, read comment
Merge pull request #79 from exside/master

New Update, read comment and UNINSTALL previous installations on your device
implemented equals in mensa and testet it for further testing
implemented database for saving and loading the User Model. Also changed save(mensalist) to update(mensalist), so the database deletes the tables before saving the new ones
Merge pull request #81 from theodortruffer/master

implemented database for saving and loading the User Model. Also changed...
tests for MensaList
Merge remote-tracking branch 'original/master'
tests for Menus implemented
new tests for the MenuList implemented
Implemented tests for Friends
Merge pull request #82 from NicolasKessler/master

First part of model tests completed
Big Update, Homescreen variations, Menu icons, List sorting, crash catching, rotation fixing, state preserving usw