Changed the calculation of transformation with those of the Render class.

Although the former implementation is more accurate we have to the same
method, otherwise the polygon used for hit testing is sometimes slighly
differently located than the polygon that has been drawn.
Added applyTransformation() method.
Reformatted.
Use more recent maven compiler plugin version 3.1.
Generate the javadoc and bind it to the jar phase.
More javadoc.
Extracted getRenderSceneArgs() method.
Moved myPolygonTest implementation to the Render class.

This should centralize where the coordinate transformation takes place.
Also removed the Ballroom.calcPolygon() method as it has no clients
any longer.
Removed unused calcPolygon() method.
Moved implementation of getPixCoordinateInfo() into the Render class.

This further unifies the place we actually deal with calculations.
Call render.getPixCoordinateInfo() directly.
Made myPolygonTest private and moved it a little bit up.
Document myPointRangeTest() and reanmed feetCoord to center.
Renamed feetCoord to center in myPolygonTest().
Use enum for foot parts.

We are dealing with a much later Java version now so we can use
proper enums.