This makes libgit2 compliant with the following scenario

$ git ls-remote file:///d:/temp/dwm%20tinou
732d790b702db4b8985f5104fc44642654f6a6b6        HEAD
732d790b702db4b8985f5104fc44642654f6a6b6        refs/heads/master
732d790b702db4b8985f5104fc44642654f6a6b6        refs/remotes/origin/HEAD
732d790b702db4b8985f5104fc44642654f6a6b6        refs/remotes/origin/master

$ mv "/d/temp/dwm tinou" /d/temp/dwm+tinou

$ git ls-remote file:///d:/temp/dwm%20tinou
fatal: 'd:/temp/dwm tinou' does not appear to be a git repository
fatal: The remote end hung up unexpectedly

$ git ls-remote file:///d:/temp/dwm+tinou
732d790b702db4b8985f5104fc44642654f6a6b6        HEAD
732d790b702db4b8985f5104fc44642654f6a6b6        refs/heads/master
732d790b702db4b8985f5104fc44642654f6a6b6        refs/remotes/origin/HEAD
732d790b702db4b8985f5104fc44642654f6a6b6        refs/remotes/origin/master