bookmarks: Add -B option to incoming/outgoing to compare bookmarks
We add a -B/--bookmarks option to hg incmoing and hg outgoing. If the option
is passed we compare bookmarks instead of changesets. This can be used
to see which bookmarks do not exists on the remote site.
created new head
digraph G {
-1 -> 0
0 -> 1
0 -> 2
2 -> 3
1 -> 3
}