Solved GAPainter resolution glitch
Added local Computing mode
Renamed network package to imageComputing

The image function classes now send their progress to a Buffer<Result>
instead of a DataOutputStream:
-for the network the Buffer is read by a Thread in the
NetworkComputationThread which converts the Result to data for the
toClient OutputStream
-for the local work the Buffer is directly read by the Client (because
no more OutputStream is needed)