Add boolean option "bones"

Setting bones off prevents saving and loading bones files.

doc/Guidebook.mn

@@ -1927,6 +1927,8 @@ quality of the weapon; you are free to manually fill your quiver or quiver sack
 or make ready
 with the `Q' command instead.  If no weapon is found or the option is
 false, the `t' (throw) command is executed instead.  (default false)
+.lp bones
+Allow saving and loading bones files.  (default true)
 .lp boulder
 Set the character used to display boulders (default is rock class symbol).
 .lp catname

include/flag.h

@@ -21,6 +21,7 @@ struct flag {
 	boolean  autoquiver;	/* Automatically fill quiver */
 	boolean  beginner;
 	boolean  biff;		/* enable checking for mail */
+	boolean  bones;		/* allow saving/loading bones */
 	boolean  confirm;	/* confirm before hitting tame monsters */
 	boolean  debug;		/* in debugging mode */
 #define wizard	 flags.debug

include/patchlevel.h

@@ -14,7 +14,7 @@
  * Incrementing EDITLEVEL can be used to force invalidation of old bones
  * and save files.
  */
-#define EDITLEVEL	55
+#define EDITLEVEL	56
 
 #define COPYRIGHT_BANNER_A \
 "NetHack, Copyright 1985-2012"

src/bones.c

@@ -287,6 +287,7 @@ can_make_bones()
 {
 	register struct trap *ttmp;
 
+	if (!flags.bones) return FALSE;
 	if (ledger_no(&u.uz) <= 0 || ledger_no(&u.uz) > maxledgerno())
 	    return FALSE;
 	if (no_bones_level(&u.uz))
@@ -533,6 +534,7 @@ getbones()
 	if(discover)		/* save bones files for real games */
 		return(0);
 
+	if (!flags.bones) return (0);
 	/* wizard check added by GAN 02/05/87 */
 	if(rn2(3)	/* only once in three times do we find bones */
 		&& !wizard

src/options.c

@@ -85,6 +85,7 @@ static struct Bool_Opt
 #else
 	{"BIOS", (boolean *)0, FALSE, SET_IN_FILE},
 #endif
+	{"bones", &flags.bones, TRUE, SET_IN_FILE},
 #ifdef INSURANCE
 	{"checkpoint", &flags.ins_chkpt, TRUE, SET_IN_GAME},
 #else