* Test redirect_uri construction
This was a test marked as TODO.
* Remove duplicate test
* Add tests to exactly match redirect URIs
* Redirect URIs must match exactly.
To quote from the specification at
http://openid.net/specs/openid-connect-core-1_0.html#AuthRequest:
Redirection URI to which the response will be sent. This URI MUST
exactly match one of the Redirection URI values for the Client
pre-registered at the OpenID Provider, with the matching performed as
described in Section 6.2.1 of [RFC3986] (Simple String Comparison).