Fix MongoDB server string
Make OAuth2_Storage_Mongo properties protected
Use spaces instead of tabs, to be consistent with the rest of the lib.
User details must have a 'user_id' field, to store in token data
Merge branch 'develop' of http://github.com/bshaffer/oauth2-server-php into develop
Merge branch 'develop' of https://github.com/julien-c/oauth2-server-php into julien-c-develop
Merge branch 'julien-c-develop' into develop