Correctly set last_nonmenu_event when replaying

Correctly set last_nonmenu_event when replaying

read_key_sequence can, in various circumstances, play back recorded
events.  Make sure that we set last_nonmenu_event as if we weren't
replaying.  Without this change, we leave last_nonmenu_event set to
whatever it was before we started replaying, leading to spurious
random keymap menu prompts appearing after reading terminal control
sequences, the translation of which sometimes causes event replays.

* src/keyboard.c:
(grow_bool_vector): New function
(read_key_sequence): Remember menu event history per-event.