[Delivers #83803032] Implement select

@mhfrantz 

This PR implements select, using a new helper method _toGroovyFunctions, but leaving hacky code in _javify that must ultimately be modified along the lines of _toGroovyFunctions. And of course, we need to reconcile with the work you began in your branch https://github.com/jimlloyd/gremlin-v3/tree/mhfrantz-implement-path.

I'd like merge this change as it unblocks the other PR we are working on, even if we expect this implementation to change once we do the above.