Added domain dimension-type methods to GenericNetwork.  These methods are roughly implemented, but should probably be subclassed by each specific network generator. - Previously there was a 'domain_size' method in Cubic, which I believe Tom duplicated in Delaunay.  These methods took several arguments and were a bit tricky to use. - I think explicitly named methods in GenericNetwork is better, but I could be wrong about that.
Added domain dimension-type methods to GenericNetwork.  These methods are roughly implemented, but should probably be subclassed by each specific network generator.
- Previously there was a 'domain_size' method in Cubic, which I believe Tom duplicated in Delaunay.  These methods took several arguments and were a bit tricky to use.
- I think explicitly named methods in GenericNetwork is better, but I could be wrong about that.


Former-commit-id: fa488c16e87c8ade6596e461c734e6dd5f7d3c1e
Former-commit-id: 7c3c1a1e9b9fc3f58c945f991cf95566de96855a
PMEAL/OpenPNM,stadelmanma/OpenPNM,amdouglas/OpenPNM,amdouglas/OpenPNM,TomTranter/OpenPNM