another man page revision

Add new '--usage' and '--help'.
Add missing '--nethackrc:RC-file' and '--no-nethackrc'.
Explain -D and -X more precisely.
Reorder the options to manually produce a synopsis section that looks
like

"  nethack [ -d|--directory directory ] [ -w|--windowtype interface ]
"  [ --nethackrc:RC-file | --no-nethackrc ] [ -n ] [ -dec | -ibm ]
"  [ -u playername ] [ -X | -D ] [ -p profession ] [ -r race ] [ -@ ]
"
"  Also [ -A|-Arc | -B|-Bar | -C|-Cav | -H|-Hea | -K|-Kni | -M|-Mon |
"  -P|-Pri | -R|-Rog | -Ran | -S|-Sam | -T|-Tou | -V|-Val | -W|-Wiz ]
"
"  nethack [ -d|--directory directory ] -s|--scores [ -v ]
"  [ -p profession ] [ -r race ] [ playernames ]
"
"  nethack [ --usage | --help ] [ --showpaths ] [ --version[:paste] ]

to avoid instances of line breaks like "...[\n-foo ]..." and
"...[ -bar\n]...".  With TeX it would be straightforward to favor line
breaks in front of "[" and after "]" but I don't know whether or how
'roff can do that.

doc/nethack.6

@@ -9,13 +9,17 @@
 .ds Nr \\$2
 ..
 .NB $NHDT-Branch: NetHack-3.7 $
-.NR $NHDT-Revision: 1.23 $
+.NR $NHDT-Revision: 1.27 $
 .ds Na Robert Patrick Rankin
 .SH NAME
 nethack \- Exploring The Mazes of Menace
 .SH SYNOPSIS
 .na
 .hy 0
+.\" Some options ordering is explicit (-d first, -u before -D), others
+.\" have been arranged to fit within an 80-column page with nearly full
+.\" lines while avoiding splitting "[" and "-opt ]" or "[ -opt" and "]"
+.\" across line boundaries.  It would be better to do that with 'roff magic.
 .B nethack
 [
 .BR \-d | \-\-directory
@@ -27,10 +31,27 @@ nethack \- Exploring The Mazes of Menace
 .BR \-w | \-\-windowtype
 .I interface
 ]
+.br 1
+[
+.BI \-\-nethackrc: RC-file
+|
+.B \-\-no\-nethackrc
+]
 [
 .B \-n
 ]
 [
+.BR \-dec " | " \-ibm
+]
+.br 1
+[
+.B \-u
+.I playername
+]
+[
+.BR \-X " | " \-D
+]
+[
 .B \-p
 .I profession
 ]
@@ -39,23 +60,8 @@ nethack \- Exploring The Mazes of Menace
 .I race
 ]
 [
-.B \-u
-.I playername
-]
-.\" -[DX] used to be before -u but on Windows and MS-DOS, '-u wizard'
-.\" needs to be present before -D in order for it to be allowed, so show
-.\" -[DX} after '-u playername' even though this man page is for Unix.
-[
-.B \-[DX]
-]
-[
 .B \-\@
 ]
-[
-.B \-dec
-|
-.B \-ibm
-]
 .PP
 Also
 [
@@ -95,6 +101,7 @@ Also
 [
 .B \-v
 ]
+.br 1
 [
 .B \-p
 .I profession
@@ -109,6 +116,11 @@ Also
 .PP
 .B nethack
 [
+.B \-\-usage
+|
+.B \-\-help
+]
+[
 .BR \-\-showpaths
 ]
 [
@@ -259,25 +271,26 @@ is already used for the
 role.
 .PP
 .B \-\@
-choose any omitted characteristics (profession/role, race, gender,
+tells nethack to choose any omitted characteristics (profession/role, race,
-alignment) randomly without prompting.
+gender, alignment) randomly without prompting.
 Otherwise, leaving out any of these characteristics will result in you
-being prompted
+being prompted during game startup for the information.
-during the game startup for the information.
 .PP
 The
 .B \-n
 option suppresses printing of any news from the game administrator.
 .PP
 The
-.B \-D
-or
 .B \-X
-option will start the game in a special non-scoring discovery mode.
+option will start the game in a special non-scoring discovery mode
+(also known as explore mode).
 .B \-D
-will, if the player is the game administrator, start in debugging (wizard)
+will start the game in debug mode (also known as wizard mode),
-mode instead.
+if the player is allowed, otherwise if will switch to
-.\" TODO? describe "WIZARDS=x y z" line from SYSCF/sysconf.
+.BR \-X
+instead.
+Control of who is allowed to use debug mode is done via the
+.RI "\(lq" WIZARDS= "\(rq line in nethack's " sysconf " file."
 .PP
 The
 .BR \-d " or " \-\-directory
@@ -302,7 +315,20 @@ Specifying a value on the command line overrides any value
 specified in the run-time configuration file.
 NetHack's #version command shows available interfaces.
 .PP
-Some options provide feedback and then exit rather than play the game.
+The
+.BI \-\-nethackrc: RC-file
+option will use
+.I RC-file
+instead of the default run-time configuration file
+.RI "(typically " \(ti/.nethackrc ")"
+and the
+.B \-\-no\-nethackrc
+option can be used to skip any run-time configuration file.
+.PP
+.\" extra blank line
+.br 1
+.PP
+Some options provide feedback and then exit rather than play the game:
 .PP
 The
 .BR \-s " or " \-\-scores
@@ -321,6 +347,12 @@ It may also be followed by one or more player names to print the scores of the
 players mentioned, by 'all' to print out all scores, or by a number to print
 that many top scores.
 .PP
+.BR \-\-usage " or " \-\-help
+will display information similar to this manual page, then exit.
+Use
+.RB \(oq "nethack \-\-usage | more" \(cq
+to read it a page at a time.
+.PP
 .B \-\-showpaths
 can be used to cause NetHack to show where it is expecting
 to find various configuration files.