system-wide configuration file

Add options SYSCF (to add a system-wide configuration file) and SYSCF_FILE
(for a file-based implementation of SYSCF) - this allows a binary distribution
to be configured at install time.  The only option supported at this time is
WIZARDS - a list of usernames which can use -D; currently only for unix-likes
but should be extendable to anything that has a concept of multiple users.
Add mac tty multiuser config using sgid.

sys/unix/hints/macosx.sh

@@ -0,0 +1,57 @@
+#!/bin/sh
+#      SCCS Id: @(#)macosx-mu.sh 3.5     2007/12/12
+# Copyright (c) Kenneth Lorber, Kensington, Maryland, 2007.
+# NetHack may be freely redistributed.  See license for details.
+#
+# hints helper script for macosx
+# DO NOT invoke directly
+
+cmd=$1
+
+case "x$cmd" in
+xuser)
+	user=$2
+	gotuser=`niutil -readval . /users/$user name 0 2>/dev/null`
+	[ -z $gotuser ] && (echo "User $user does not exist."
+		exit 1;
+	)
+	exit 0
+	;;
+#name: dummy1
+#_writers_passwd: dummy1
+#_writers_tim_password: dummy1
+#_writers_picture: dummy1
+#home: /Users/dummy1
+#gid: 504
+#picture: /Library/User Pictures/Animals/Dragonfly.tif
+#uid: 504
+#hint: dummy1
+#_writers_hint: dummy1
+#sharedDir: 
+#_shadow_passwd: 
+#_writers_realname: dummy1
+#shell: /bin/bash
+#passwd: ********
+#authentication_authority: ;ShadowHash;
+#realname: dummyname1
+#generateduid: F6D4991C-BDF5-481F-A407-D84C6A2D0E2A
+xgroup)
+	group=$2
+	gotgrp=`niutil -readval . /groups/$group name 0 2>/dev/null`
+	[ -z $gotgrp ] && ( echo "Group $group does not exist."
+		exit 1
+	)
+	exit 0
+	;;
+#niutil -read . /groups/bin name 0
+#name: bin
+#gid: 7
+#passwd: *
+#generateduid: ABCDEFAB-CDEF-ABCD-EFAB-CDEF00000007
+#smb_sid: S-1-5-21-107
+#realname: Binary
+
+*)      echo "Unknown command $cmd"
+	exit 1
+        ;;
+esac