Take care of a Qt TODO: when using 'popup_dialog' and entering
a count during a yn#aq question, change the default answer button
from 'n' to 'y' since ending the count with <return> accepts it.
When 'popup_dialog' is set, the Qt interface uses a popup window
for yn_function() calls and the dialog has a list of buttons, one
per potential choice. It has been handling "yn?" and "ynq?"
questions differently from general request-one-char prompts, using
buttons "Yes", "No, and "Cancel" instead of showing individual
letters. This extends that to "ynaq" and "yn#aq" questions and
labels 'q' reply as "Stop" instead of "Cancel" for those. Also,
when player uses keyboard instead of mouse to answer, allow 'c'
as well as 'q' for cancel ones, 's' as well as 'q' for stop ones.
Prompt Buttons
yn [Yes ][ No ]
ynq [ Yes ][ No ][Cancel]
ynaq [Yes ][ No ][All ][Stop]
yn#aq [Yes ]Count:______[ No ][All ][Stop]
rl [ Left ][Right ] //unchanged; included for completeness
(For contrast, when something specifies "ny" as the acceptable
choices, the buttons will just be [n][y]. Prompts for choosing
from a list of inventory letters can't accidentally match these
special cases as long as they're specified in alphabetical order.)
For Qt with 'popup_dialog' On, fix number entry when user types
a digit (or '#') directly onto the dialog instead of clicking
inside the Count box and then typing. Before, that first typed
digit was starting out as selected, so typing the next digit
replaced the selection instead of getting appended to the string
of digits being constructed. Fixed by moving the relevant code
to the KeyPress handler instead of re-executing the dialog.
Also, if a keypress is just a modifier, ignore it. The next
event should be the actual character. Prevents treating <shift>
(and <caps lock>!) as useless dialog responses. Before this,
attempting to type '#' to initiate a count wouldn't work because
the <shift> part of shift+3 ended the dialog. Now '#' works
(and is still optional; starting with a digit suffices).
