Add an option to undo and redo motions

[godalming123]

I think that there should be an option to undo and redo motions/changes to the selection. This is similar to #12877, but more broad, since not only can you go back when you press <A-.> too many times, but you can also go back if you use any other wrong motions, which is especially useful for multi cursor, since it takes a couple keystrokes to re-setup your cursors in the right places if you accidentally use a motion which is not reversible. Here's a list of non-reversible motions:

• , (keep primary selection)
• <A-,> (remove primary selection)
• ; (collapse selection)
• gl (goto line end)
• gh (goto line start)
• n and N (select next and previous search match)
• <A-.> (repeat last motion)