fixed bug in the helper-class in which the FileExist() method returns true although the file is not in the /res/ directory. issue #147 can be closed.
fixed bug in propertyGrid in which an exception has been thrown, if an query has been added through the propertyGrid, if no query was defined before.
Merge branch 'WorkBareus'

Conflicts:
	Editor/Controller/EditorController/PreviewController.cs
readded height/width
Merge branch 'WorkBareus'