More cleanup of Region, Location and Screen

Important changes
* Some unneeded, obsolete or misunderstandable methods were removed
* ROI for Screens removed because it was barely used and not well implemented
* Cropping of Regions to Screen size removed because this cannot be controlled consistently (e.g. x and y can be set directly without setter)
* Removed "ActionRobot" that handled all mouse actions before with a separate Robot for each Screen.
* Removed translation of coordinates between Sceens when searching in regions on different screens, making it possible to work with screen relative positions
* UnionScreen will be implemented in the future as a global screen with global coordinates to allow an easy working without manual coordinate translation