bp/api-error-codes

bp/api-error-codes
Restructured API error codes for Quantum API v1.1
This changeset provides the following changes:
- Only standard HTTP errors for Quantum API v1.1
- Customized fault response body formatting according to API version
- Changes to unit tests to deal with version specific status codes

NOTE: Client side changes are not in this branch.
They should be implemented within bp/quantum-client-1.1.
NOTE-2: Fixing references to QuantumHTTPErrors in extensions framework

Change-Id: I56f50b5c59d73fd6f02905106f0c2a3c8341a741