Added exceptions when loading projects has errors
UtilFile.java/loadExistingOrCreateStandardDroneProject updated
DroneBrickLayoutTest.java/testBricksPrototypeView updated
MainMenuActivityTest.java/testLoadProject modified
MainMenuActivityTest.java/createTestProject modified
Merge pull request #994 from Catrobat/mj7007-refactorLoadProject

fix CAT-814 with pull request issue CAT-940 : Exceptions for Loading Projects