Merge branch 'file-loading' into dev-6-0

Conflicts:
	PlayWall/assets/de/tobias/playpad/assets/lang/_de.properties
	PlayWall/src/de/tobias/playpad/PlayPadImpl.java
	PlayWall/src/de/tobias/playpad/PlayPadMain.java
	PlayWallCore/src/de/tobias/playpad/Updatable.java
	PlayWallCore/src/de/tobias/playpad/action/ActionSerializer.java
	PlayWallCore/src/de/tobias/playpad/pad/PadSerializer.java
	PlayWallCore/src/de/tobias/playpad/project/Project.java
	PlayWallCore/src/de/tobias/playpad/project/ProjectReference.java
	PlayWallCore/src/de/tobias/playpad/project/ProjectReferenceSerializer.java
	PlayWallCore/src/de/tobias/playpad/settings/ProfileReference.java
	PlayWallCore/src/de/tobias/playpad/settings/ProfileReferenceSerializer.java