Add support for jsonrpc4j

[breedx-splk]

It would be great to have instrumentation for https://github.com/briandilley/jsonrpc4j.

The matching could get a little interesting, because this library includes support for:

• client
• server
• spring remoting
• dynamic proxies
• spring + annotation-based autodiscovery

We could definitely start small with just server and then add additional issues to support client and then others (as it makes sense to).

[trask]

linking in related(?) issue #5995

[chenlujjj]

Hi @trask , I am working on it, I'd like to create a PR in the near future, maybe next week