libgit2/libgit2 — pull request #1919 by carlosmn (2013-10-30 15:21:56+00:00)
Title: protocol: basic support for multi_ack_detailed

This tells the server that we speak it, but we don't make use of its
extra information to determine if there's a better place to stop
negotiating.

In a somewhat-related change, reorder the capabilities so we ask for
them in the same order as git does.

Also take this opportunity to factor out a fairly-indented portion of
the negotiation logic.