guard against invalid remotes passed to git lfs push

[technoweenie]

Fixes #973

[sgoo]

Should this also be applied to pre-push?
If I do:

$ GIT_TACE=1 git push http://sgoo@git-server.com/sgoo/test.git
...
12:47:18.836067 git.c:561               trace: exec: 'git-lfs' 'pre-push' 'http://sgoo@git-server.com/sgoo/test.git' 'http://sgoo@git-server.com/sgoo/test.git'
...

You can see pre-push is invoked with the URL I provided to git push. But the request that is made in pre-push is made to the remote configured as origin.

[technoweenie]

deleted

[technoweenie]

WOW, I thought you were replying to #971 for some reason. Ignore everything I said in my last reply. I'll take a look at pre-push.

[technoweenie]

Thanks for the feedback! I added it to pre-push as you suggested.