code formatting
implemented call graph scene creation, toggeld by key 'c'
removed unused imports
introduced different appearances for usage edges and inheritance edges
renamed package model to layout
moved relevant classes into layout package
ignore null vertex nodes when connecting vertices
moved unit test for layout classes to new layout package
moved test to scenegraph package
fixed bug: multiple methods calls from class A to B are not stored as
edges in call graph. Fixed by using DirectedMultigraph.
changed package of unit test
implemented condensed graph builder, which reduces the number of edges
of a multigraph to one.
using condensed call graph for building scene, only one line per usage
will be drawn
Merge branch 'feature/displayCallGraph'
added development tool for designing 3d materials. will be moved if a
module for this tool is needed.
Added snapshot version of jgrapht instead of old outdated version from sourceforge. JgraphT needs to be checkedout locally and build with mvn install!