Change the initial <c-h>/<c-k> bindings to the recently freed-up
<a-u></a-U>.
Pros:
- easier to remember
- the redo binding is logical.
- works on legacy terminals, unlike <c-h>
Cons:
- It's less convenient to toggle between selection undo and redo
keys. I think this is okay since this scenario does not happen that
often in practice.
7d2bae63b9
