Added radio button list in interface for projector selection. Use this selection for the current calibration.
Changed setup / show mode from a toggle to a Radio button for clarity. Made the selection of a picture vs a video vs one of the other rendering modes explicit in the control panel, so that we can always select the picture interactively (e.g. for calibration purposes, to prevent the calibration from being inside-out)
Major restructuring: projectorView and modelView are now owner of the functionality they should have, and which was originally performed by 'testApp'. They do their own drawing and updating. Access to specific variables has been made more explicit, for example by passing a referencee to the main control panel as a parameter to the draw() function. This structure makes it much easier to extend and understand the system, for example for the desired situation to have a main (laptop) screen that contains all the GUI, and separate 'screens' for the projectors. These are then viewports inside a large window that is stretched over a large virtual desktop.