Add connstring to config (noop for now)
Add unsafeLoginSecret to config

This is to be used when logging in from a mobile device, with just a Facebook or Twitter ID to go off of.
Mock Twitter interface
Rename for clarity (noop)
Update createUser function + add UC#register
Update findBy[social] methods + remove UC#user

UserCollection#user was clunky and bad, so removed it in favor of using more specific methods.

Also the findByFacebook/Twitter/Username/Email methods have been updated to return a single record if a single key is passed, an array if an array is passed, and false if no users are found.

Finally, updated authentication to use unsafeLogin + have a more intuitive API.
Add UserCollection#updateUserPassword
Enable Bluebird long stacks by default
Pretty stack trace Error Middleware
Call createUser correctly
Validate user on save (required fields + unique)