New project: "Spot the Diff"
Added ZIndex + Memory Optimization

+ two checks to prevent null errors.
GUIButton: No text/font necessary anymore
ZIndex works now for all GUIElements
First part of "Spot the Difference"
New field for all GUIElements: Tag (object)
Merge remote-tracking branch 'origin/feat_text_gui' into feat_as_rocketgame
New Goal class ... and less memory munchies