b4 review: reply to a patch note + misc.

Hi Konstantin,

When a patch has a note under 3 dashes, the note is dropped when the
patch is applied during a review, as expected. Except that it also means
the note is no longer there when replying to a patch from b4 review tui.

Do you think the "Reply" view could use the email from lore instead?

While at it, some small ideas:

- I find it "too easy" to quit the "Review" view: I'm on a patch,
  checking follow-up comments, etc. then if I hit an extra 'q', I'm
  back on the "Tracked" list, switching back to another commit in git,
  etc. Maybe a "confirmation" question could help? Or a different short
  key?

- When I press the 'review' button, I need to specify the commit/branch
  for the new base. I usually prefer to apply it on top of the current
  HEAD, but I'm not sure how to force b4 to suggest that by default. I
  tried using "git config b4.review-target-branch", but it still guesses
  something else.

- Could we eventually have a template for the replies? It would be good
  to automatically add a header (Hi <first name>,) and a trailer (like
  here at the bottom).

Cheers,
Matt
-- 
Sponsored by the NGI0 Core fund.