Merging the brand new Quantum-client-library feature.

Thanks to lp:tylesmit for this contribution to the Quantum project.

All, client, CLI, dashboard, Quantum API client, should now start
using this client library as our defacto "SDK" to program against
Quantum's Cloud Networking fabric.

added:
  quantum/client.py
  tests/unit/api.py
modified:
  quantum/cli.py