Ticket #3140: mcedit: trailing newline check applied too early when exiting.

(edit_ok_to_exit): check newline after user wants to save file.
(edit_check_newline): fix message.

Signed-off-by: Andrew Borodin <aborodin@vmail.ru>
Merge branch '3140_check_newline'

* 3140_check_newline:
  Ticket #3140: mcedit: trailing newline check applied too early when exiting.