some cleanup

next: mv Zork GraphDirected
moved Zork.java
GraphDirected passing preliminary test.

next: add more tests. rename to DirectedGraph etc. add UndirectedGraph. implement House.
added more GraphDirected tests. GraphDirected.equals and hashCode

next: GraphUndirected. add House
renamed GraphDirected to DirectedGraph

next: implement UndirectedGraph. add House
UndirectedGraph passing tests

next: add logging. merge UG and DG tests, clean up code
Code cleanup, added Debug class, fixed external lib dependencies.

next: readme, House class