* added an RFC 7662 compliant OAuth2 auth adapter
* forgot to add the actual auth adapter to the previous commit
* fixed lint errors
* * added test coverage
* changed option names in auth adapter from snake case to camel case
* added underscore prefix to helper function names
* merged consecutive logger calls into one call and use JSON.stringify() to convert JSON objects to strings
* changed error handling (ParseErrors are no longer thrown, but returned)
* added description of the "debug" option and added this option to the tests too
* added a check of the "debug" option to the unittests and replaced require() of the logger with an import (the former does not work correctly)
* added AuthAdapter based auth adapter runtime validation to src/Adapters/Auth/index.js, added capability to define arbitrary providernames with an "adapter" property in auth config, replaced various "var" keywords with "const" in oauth2.js
* incorporated changes requested by flovilmart (mainly that oauth2 is now not a standalone adapter, but can be selected by setting the "oauth2" property to true in auth config
* modified oauth2 adapter as requested by flovilmart
* bugfix: defaultAdapter can be null in loadAuthAdapter() of index.js (my change broke the tests)
* added TODO on need for a validateAdapter() to validate auth adapters
* test cases and cleanup
* Use the correct function when validating google auth tokens
httpsRequest.request expects the param postData and has no default value
or validation to check if it is missing before using it. As a result, an
error `TypeError: First argument must be a string or Buffer` is
thrown when an attempt is made to authenticate with Google.
A quick check on the LinkedIn, FB, and twitter authentication adapters
shows they are using httpsRequest.get for their validation calls.
* Correct google auth adapter tests
* Refactor all auth adapters to reduce duplications
* Adds mocking and proper testing for all auth adapters
* Proper testing of the google auth adapter
* noit
* Integrate auth adapter for Facebook accountkit login
* Also verify Facebook app id associated with account kit login
* Add appsecret_proof as extra graph request parameter
* Specific error message for Account kit and more test coverage
* One more test to cover when AppIds for Facebook account kit not configured properly
* Moves all authentication providers to Adapter/Auth
* refactors specs
* Deprecates oauth option in favor of auth option
- Deprecates facebookAppIds option (in favor of auth.facebook.appIds)
- Adds warnings about the deprecated options
* nits
