On Fedora 21 please update the git package to v2.2.2, this version is already available on Fedora 22.
Thanks & BR
Why you need newer vesrion of git in F21? What funcionality is interesting for you?
What I see in logs, there isn't anything so important that it should be reason for rebase to newer version. Newer git is going to be part of next release and if you want newer git on your machine, you should install it manualy from upstream repo.
If you need fix for some bug, create please new bugzilla for this bug and I will fix it. If fix exists in newer version, link to commit with patch could forward fix in F21.
Well, right now i just want to use the latest release, so i'm gonna to install it manually.
If other peoples want to use the latest version on F21, I've created a copr repository with git version 2.3.0: https://copr.fedoraproject.org/coprs/fabio/git/