implement oauth 2.0 authorization code workflow
Merge branch 'master' into authorization-code-workflow

Conflicts:
	src/Synapse/Controller/OAuthController.php
	src/Synapse/Provider/OAuth2ServerServiceProvider.php
Merge pull request #43 from synapsestudios/authorization-code-workflow

Add OAuth 2.0 authorization code workflow
Merge branch 'master' into implement-io-docs