Uses new cookies for persistence.

Resolves [RAVE-1265](https://issues.apache.org/jira/browse/RAVE-1265) and [1264](https://issues.apache.org/jira/browse/RAVE-1264)

- We no longer talk to the server to log out. We just destroy our cookie
- Remember me now works. This relies on an update to the mock API where we store the token in a database.