Partner Monitoring

Pretty big PR.  Didn't squash because there are several upstream merges.

* Adds a "Monitoring" tab and enables pulling-in New Relic and/or AppDynamics monitoring support
Sigh.

Yes.  I'll admit to a certain amount of experimentation.  Not for this review thread, but I had a long discussion with Meijer @ ScalaDays concerning matching vs dynamic dispatch.

Will clean up.