add a master off/on switch for sounds

sounds can be set in the config file or on the fly with the Options menu.

This also adds a mechanism for specifying a terminology preference
for a boolean option in the options menu.

The choices are: Term_False, Term_Off, Term_Disabled

Term_False, the default, will use the terms "false" and "true" in the
Options menu.
Term_Off will use the terms "off" and "on" in the Options menu.
Term_Disabled will use the terms "disabled" and "enabled" in the Options
menu.

I didn't review any of the existing options to see if one of the new
alternative terms might be a better fit. They were all left at the default.

doc/Guidebook.tex

@@ -46,7 +46,7 @@
 \author{Original version - Eric S. Raymond\\
 (Edited and expanded for 3.7 by Mike Stephenson and others)}
 %DO NOT REMOVE NH_DATESUB \date{DATE(%B %-d, %Y)}
-\date{December 28, 2022}
+\date{January 30, 2023}
 
 \maketitle
 
@@ -4903,6 +4903,9 @@ order by count, low to high; ties broken by internal index.
 Can be interactively set via the `{\tt m O}' command or via using
 the `{\tt m}' prefix before the \#vanquished command.
 %.lp
+\item[\ib{sounds}]
+Allow sounds to be emitted from an integrated sound library (default on).
+%.lp
 \item[\ib{sparkle}]
 Display a sparkly effect when a monster (including yourself) is hit by an
 attack to which it is resistant (default on).  Persistent.