Update to Jersey 2.x

https://www.pivotaltracker.com/story/show/52200823
There's something funny about how Spring and HK2 interact with optional dependencies. HK2 throws a fit if Spring doesn't deal with them, but using the HK2 annotations seems to work just fine.

At some point, someone who knows something about DI ought to take a look across the project and make sure we're ok. @ajs6f?