Subject: Add proto v2 archive command with HTTP support

From: Josh Steadmon <[email-masked]>
Date: Tue, 11 Sep 2018 22:35:16 -0700

This series adds a new protocol v2 command for archiving, and allows
this command to work over HTTP(S). This was previously discussed in [1].
I've CCed everyone who participated in that discussion.

[1]: https://public-inbox.org/git/CANq=[email-masked]/