Add a fixture for Keystone version discovery

As we push out the session and expect people to test with proper URL
responses we should provide a means to create a correct Keystone version
list to test with.

Change-Id: I8309ab6cbc47ad159f3c6e018b60ff8c15c6d917
Modify oauth calls to expect urlencoded responses

Previously, the server side would send jsonwrapped urlencoded
responses. Now we are removing the jsonwrapped portion so that
the responses for oauth calls are just urlencoded.

Related-Bug: #1336910
Change-Id: I0431a581a5c3fca38e22751ef9bde034f0a89a30
Merge "Modify oauth calls to expect urlencoded responses"