Added Decision Tree class.
Added no repetition unit test work on decision tree.
Extracted MatchTableModifier class from IslandConflictResolver class. Create edges in decision tree for repeated phrases.
Refactoring: separated the logic from the data structure.
Refactoring: separated out the travel functionality from the unit test.
  Refactoring: Separated variant graph builder utility method out of DecisionTreeCreator class.
Associate a cost with each edge; improved testability.
Made MatchTable class read only. Extracted MatchTableSelection class from MatchTable.
Refactoring: Moved use of Archipelago out of IslandConflictResolver to
MatchTableSelection.
Refactored. Removed all dependencies on Archipelago from the
IslandConflictResolver and MatchTableLinker classes.
Updated decision tree creator code to work with latest head revision of the master branch.