Auto merge of #2885 - nelhage:ssh-retry-loop, r=alexcrichton
authorbors <bors@rust-lang.org>
Sun, 17 Jul 2016 00:44:09 +0000 (17:44 -0700)
committerGitHub <noreply@github.com>
Sun, 17 Jul 2016 00:44:09 +0000 (17:44 -0700)
git: only attempt ssh-agent authentication once

This prevents infinite looping if ssh-agent authentication fails.

closes #2845


Trivial merge