Port To Jersey 2.x

Note that this relies on a forked branch to Metrics for the same purpose of supporting Jersey2 that hasn't been accepted yet. The PR for that is at https://github.com/dropwizard/metrics/pull/532


I'm in the process of applying the code review comments. I made this static because it looked more like a utility function and does not need or use any member variable from its containing class. Do you still recommend it stay non-static?