Merge pull request #17 from valhalla/dwn

GraphTile fix
comment out name display
Merge pull request #18 from valhalla/gdg

comment out name display
remove memory leaks from graphreader cache. update graphid to have a non java looking hash method
remove javaesque hash function
simplify graphreader cache interface. update graphtile to use smart pointer for internal memory so it can easily be copied and destructed automatically
Merge pull request #20 from valhalla/kk_leakhash

Fix Leaks, Use std::hash, Use shared_array
Add opposing edge index. This is the index into the edges at the end node
of the current directed edge that represents the opposing directed edge back
to the start node of the current directed edge.