BuilderUtils deleted. Its functionality has been moved to other places (see next commits)
getImageDimensions() moved to Platform. Only desktop impl provided for now
unzip() moved to new ZipUtils class. ZipUtils has also received zipping methods from Exporter.
Note: ZipUtils is placed in exporter for now, but should be moved elsewhere with no editor dependencies at some point.
ForceExit param added to EngineDesktop so demos can be launched several times
DemoBuilder:Most of the comments addressed and changes in the API reflected
Minor change in DemoLauncher - Travis did not like a constructor. Java api versions issue? Hope this fixes it