Implement CommitDelta RPC
Conversation: https://gitlab.com/gitlab-org/gitaly/issues/566
This MR implements CommitDelta
RPC under the Diff
service. It's been made a separate RPC so we can control how much deltas can go in a message, as deltas should be way smaller than actual diffs (due to the absence of chunks). GitLab-CE calls to Commit#raw_diffs(deltas_only: true)
should be handled by this RPC.
Edited by Andrew Newdigate