FFJ-12 added new parameter callbackURL to configuration and to getOAuthAccessToken/setOAuthAccessToken methods as additional parameter
FFJ-12
* getCallbackURL renamed to getOAuthCallbackURL.
* added 'oauth.callbackURL' configuration property to PropertyConfiguration
* added getOAuthCallbackURL/setOAuthCallbackURL
FFJ-12 finishing
FFJ-13 appsecret_proof support
Version 2.0.3