Mutual dependency between QvLib and BspLib

[tribad]

There are a dependency between the QvLib and the BSPLib. Each one is using functions of the other library.
But on a closer look. In QvLib the dependency only is needed in QvTraverse.cpp. I think these Functions should be moved into the BspLib and there into the VrmlFile.cpp

The developers of the QvLib may have thought it was a good idea to let the traversal of the node-tree be part of the specific user of the QvLib. So the user of this lib is the BspLib and so the implementation of these Methods should be done in BspLib.

[tribad]

The best would be to make it more classes.
This would allow us to better incorporate more fancy usage to the libraries without touch them all the time. Maybe extending it to VRML2.0 or XSD?