I/O
Merge branch 'master' 
Conflicts:
	GraphVisualisierung2/src/ch/bfh/bti7301/hs2013/gravis/core/GravisCore.java
	GraphVisualisierung2/src/ch/bfh/bti7301/hs2013/gravis/core/graph/GraphManager.java
	GraphVisualisierung2/src/ch/bfh/bti7301/hs2013/gravis/core/graph/IGraphManager.java