Merged oauth2 branch

I merged the oauth2 branch into master. I also added the request object to invalidClient/RequestUri methods. 

It seems that master does currently not build. I had to disable the netty-uploads module. Further the tests don't work. Is that a known problem?

Therefore, I tested the merged code with our backend, which currently uses unfiltered 0.6.4 and my extracted oauth2 module (kodemaniak/unfiltered-oauth2). From what I can tell, everything should work.