Feature/auth service integration

Integration of COOPR server and External Authentication service from CDAP project. As was discussed before with @sreevatsanraman , I used dependency to the cdap repo, but in future it should be replaced with dependency to the common repo. 
Also, I copied class ```SecurityAuthenticationHttpHandler``` from the ```cdap-gateway``` package. This class also could be reused, so @sreevatsanraman , could you please move this class to the common auth service too? Then we could delete it from this repo. 
@albertshau , please take to review this PR.

I'm not sure about all settings, because some of them are used directly in the auth service and for now this service has many not universal parts. I hope, after refactoring in the cdap repo we will have such ability to use custom property names.