Export / import bookmark structure and clone source info

It's generally not useful to take local bookmarks between machines, but it would be useful to be able to recreate the local set up by exporting the bookmarks with their source URLs, gleaned from the remote info of each.

Ideally it would be good to be able to export the bookmarks structure and names, the clone URL (primary remote), and possibly even ancilliary remotes and other repo settings (would probably require a dump of the .git/config / .hg/hgrc). Then when importing you should be able to fire off a bulk clone operation which reconstructs the bookmarks and repo clones on the new machine.