Couchbase Storage Backend

We're planning to implement Couchbase Storage Backend. Do you have any recommendation or advice, we would like to move it to the upstream later on?

The issue names no files, tests, entry points, or defined acceptance criteria. Start by clarifying the proposed Couchbase storage backend's scope and JanusGraph's upstream contribution requirements; identify the relevant storage-backend interfaces and tests before estimating the work. Done would require an agreed design and a defined path to upstream acceptance.

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