More OS X improvements

OS X improvements by MaddTheSane.
Refactoring and fixes from adrian17

Refactoring and fixes from adrian17.
Merge remote-tracking branch 'GabuEx/master'

Conflicts:
	osx/AppFileStaging/Contents/Info.plist
	osx/ApplicationSupportBridge.cpp
	osx/ApplicationSupportBridge.h
	osx/SDLMain.mm
	src/CaseContent/Dialog.cpp
	src/FileFunctions.cpp
	src/ResourceLoader.h
	src/Utils.h