Enable existing wc_popup_dialog option. Use it in yn_function()
instead using a mystery value which apparently used to live in Qt
Settings but isn't there anymore so couldn't be turned on or off.
Also replaces conditional USE_POPUPS which isn't defined anywhere
either so presumably came from CFLAGS and only supported "yn?",
"ynq?", and "rl?" with hardcoded Qt popups rather than using
NetHackQtYnDialog.
Doing that revealed that the popup dialog for ynaq was in pretty
bad shape. It's functional but still needs a lot of work, beyond
the limited Qt/C++ capability I possess. The KeyPress issue which
accepts <shift> as input, thereby preventing <shift>+<character>
from being typed during ynaq prompting, is particularly nasty.
Append the ynaq dialog's response to the message line containing
the corresponding prompt similar to what's now done for regular
yn_function().
Add getlin() prompt+response to the message window.
152187870c