factory entry for FFSampling prepared
added ForestFireWalker
added a BaseWalker for BFS-like Sampling algorithms as the differences between BFS, FF, RDS and SB are very small
testing BFSBaseWalker structure
removed unnecessary fields in child classes
changed data structure from List<Node> to Deque<Node> to provide a more clear Q functionality
Merge branch 'feature/algorithm-forestfire' into develop
added DFSWalker
factory for dfs and small tests in the workflow
CondonKarp Parameters found for nice distinction of communities
refactoring to provide correct Q functionality (add nodes at the end of the Q)
Merge branch 'feature/algorithm-dfs' into develop