Changed signature of request validator validateScope() method - now takes in two sets, one of the request scope and one of the client scope
Made two validateScope() methods, one for the AuthorzationEndpoint and one for the TokenEndpoint.
set the client ID on the token request from the principal, if needed
added in ClientDetails reference to createTokenRequest to allow loading of client_id parameter from authenticated client in addition to or in lieu of parameter request
moved double check inside null safe test
Fixed unit tests and changed how the clientId tests are performed in token endpoint