fix ConcurrentModificationException in ColoDialog
Merge pull request #200 from Catrobat/ConcurrentModificationException_fix

fix ConcurrentModificationException in ColoDialog
accepted: @X4mp [ru]
fixup BitmapIntegrationTest testcase
fixup testSaveLoadedImage Test in MenuFileIntegrateionTest
added write permission to test manifest
removed createNewFile() for load test

fixed bitmapIntegration centerBitmap test

added wait to stampTool button test