User story: Error on Authorization Server

[nbarbettini]

Given

• The user enters invalid parameters, or the Authorization Server configuration is wrong
• The Authorization Server will redirect back with error information, like: http://localhost:5000/debug?error=invalid_scope&error_description=The+requested+scope+was+not+valid.

The application should

• Display the error, error_description, and/or error_uri information to help the user fix the problem

[nbarbettini]

This works, just needs some client-side testing.