Git-gui does not add most of the remotes to the 'push' menu
since they are missing the "Push" line in their remotespec.
In that case, removing the remote would end up with an error.
Signed-off-by: Petr Baudis <pasky@suse.cz> Signed-off-by: Shawn O. Pearce <spearce@spearce.org>