Add example Okta Configuration to login.yml
Document POC for integration with Okta
Catch bad responses from UAA and display friendly error message.

[#76382728] https://www.pivotaltracker.com/story/show/76382728
Fix verification of service call.
Add in ability to load SAML metadata from classpath
Add in simple Okta sample metadata file that points to an Okta preview channel. Use this as an example of how an Okta file looks like
https://www.pivotaltracker.com/story/show/76721986
[#76721986]
Update docs with quick and easy standalone configuration.
https://www.pivotaltracker.com/story/show/76721986
[#76721986]
Add in login.yml example