Added tests for methods to modify Node weight
Added code for methods to modify Node weight
Added damping factor and wrote tests for functions that calculate the new weights and update the nodes with them.
Added tests for getEdgeCardinality and expanded existing test for UndirectedGraph.getNodeEdges
Added code for getEdgeCardinality
Added code and fixed test for calculateNewWeight
Added code for prepareNewWeights and fixed miscalculations in tests
Made internal methods protected and added runAlgorithm method that puts them together