Bugfix: cannot push to scp style URL
Bugfix: cannot push to scp style URL

When push to a scp style url, like:

    git push git@github.com:git-lfs/git-lfs.git HEAD

Git-lfs will complain about bad url.  This is because golang 1.8 has
changed the implement of `url.Parse` method.  It will fail with a nil
pointer and an error if the remote url is a scp style URL.

Make a golang compatible test, I.E. check null pointer, then check u.Scheme.

Signed-off-by: Jiang Xin <6bb97c20172014585c1cb9cfa7ac10e0c9ba0ecd@huawei.com>

Jericho25/-git-lfs_miilkyway,github/git-lfs,Jericho25/-git-lfs_miilkyway,andyneff/git-lfs,aleb/git-lfs,dakotahawkins/git-lfs,aleb/git-lfs,github/git-lfs,andyneff/git-lfs,Jericho25/-git-lfs_miilkyway,aleb/git-lfs,github/git-lfs,andyneff/git-lfs,dakotahawkins/git-lfs,dakotahawkins/git-lfs