Graph: added new generic parameter E extends Edge
DirectedGraph: fixed
DijkstraAlgo: removed old, partly implemented new
deleted: SearchGraph, SearchGraphReader
SearchItem: added
DepthFirstSearch: new implementation
Graph: added edges()
Graph: changed Collection to List in getIn, getOut, edges
RandomContraction: removed old, partly implemented new
DijkstraAlgo: implemented
Station: added
deleted: DijkstraGraph, ContractionGraph
ReversibleGraph: deleted
KosarajuAlgo: partly implemented