Fixed a bug in BTree when duplicate keys caused a infinite loop
Fixed an accidental check-in of the DataStructures class
Added a hashCode method if an equals() method is defined
Fixed a bug in Johnson's algorithm and commented/cleaned up the graph algorithm classes
Moved the Graph related tests to their own file
Cleaned up the graph classes
Added a equals() and hashCode() method to Graph.CostPathPair
Moved the Graph related tests to their own class
Moved the Graph related tests to their own class