Contains the implementation of the abstract plotter functionality of 2D plots

The package contains an abstract Plotter2D and abstract DrawingPane.
Both provide the basic functionality of every 2D Plot. Beside others this is the selection tangle handling and cursor painting (cross hair)
There is also a default Header implementation which is not abstract as assumed to be reusable when needed. The Plotter2DScrollPane and the Plotter2DScrollPaneLayout are subclasses of the default ScrollPane and ScrollPaneLayout to rearange the headers.