User create, login and logout support
Return the nameForRestUrl to be used by UserRepository for contract creation
login and logout with access token

Reworked User login and logout to work with access token properly.
Access token set and removed from header
Implemented feedback from pull request

Replaced tabs with 4 spaces,
userLogin passes through AccessToken
new helper class logins and passes back User
User Unit Tests
User and File/Container tests
Code clean-up

Includes fix of failing unit-tests.
Add include=user to UserRepository.login

Modify LoginCallback and remove GetLoggedInUserCallback.
Merge pull request #27 from strongloop/feature/user-model

Implement User model