Link to docs - leave minimal README.

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Refactor models into json definitions
Use app.middleware to register handlers
Allows email/username for login
Add relations to oAuth models
Fix the JWT parsing
Export authenticate as a factory to middleware chain
Add refresh token generation
Update deps
Merge pull request #6 from strongloop/feature/componentize-oauth2

Feature/componentize oauth2
Tidy up the endpoints based on tests from strong-gateway
Tidy up validation of code and token
Tidy up missing user/app id error handling
Remove obsolete tests
Merge pull request #8 from strongloop/feature/componentize-oauth2

Tidy up validation of access tokens/authorization codes
Update deps
v2.0.0-beta1
Merge branch 'release/2.0.0-beta1' into production