Renamed NavMesh and NavMeshDetail to PolyMesh and PolyMeshDetail respectively.
Renamed PolyMeshDetail.TrisInfo to TriangleData.
Renamed PolyMeshDetail.MeshInfo to MeshData.
Properly named MeshData fields.
Continued renaming references to NavMesh[Detail] to PolyMesh[Detail].
Other small refactors.