Consider disentangling Shibboleth authentication from Production configuration

[kerchner]

Currently Shibboleth authentication is hard-baked into the Production configuration. We can decide to:

• Accept this and consider the scholarspace-test environment as the place to test code with production configurations. A drawback of this is that the test environment can get messy with multiple people all modifying it.
• Create a "dev" Shibboleth identity provider (IdP) that can authenticate requests coming from anywhere (e.g. dev servers, EC2, etc.)
• Create a configuration in the code that turns Shibboleth Authentication on or off (where "off" defaults to local Sufia user account management)