TINKERPOP-2075 Added ReferenceElementStrategy

[spmallette]

https://issues.apache.org/jira/browse/TINKERPOP-2075

This strategy converts all graph elements to references. Configured this strategy in Gremlin Server by default for the example graphs. Made a few minor updates to tests that were assuming the return of "detached" elements.

All tests pass with docker/build.sh -t -i

VOTE +1

[dkuppitz]

Do you have a scenario in mind where providers would construct a new ReferenceElement step? I don't think it's necessary and I guess if you would have thought of such a scenario, you wouldn't have nested the class inside ReferenceElementStrategy; hence I think ReferenceElement constructor can be package-private.

Anyway, since this is just a minor thing ...

VOTE +1

[spmallette]

yeah.........i'll sleep on that. wasn't sure what to do with it. such a dumb little step.

oh, i wanted to ask....this should be a finalization strategy right? i tried it as a decoration at first and it didn't work right, so i figured it needed to be applied at the end and that seemed to fix things. 🤷‍♂️ should i have done something else?

[dkuppitz]

No, FinalizationStrategy is correct, nothing else to do here.