new makemon() flag

add a flag to makemon() to allow monster to be created adjacent to the supplied  coordinates if there is already a monster at the target location

doc/fixes34.2

@@ -106,6 +106,8 @@ never display I symbol on the mounted hero/steed location
 pit digging is no longer stopped by a sleeping monster next to you
 ensure mksobj() always attaches timer to corpse, even if called with init FALSE
 only charge for eating one stacked tin, not all at once
+add flag to makemon() to allow monster to be created adjacent to the supplied 
+	coordinates if there is already a monster at the target location
 
 
 Platform- and/or Interface-Specific Fixes

include/hack.h

@@ -140,6 +140,7 @@ NEARDATA extern coord bhitpos;	/* place where throw or zap hits or stops */
 #define MM_NONAME	  0x20  /* monster is not christened */
 #define MM_NOCOUNTBIRTH	  0x40  /* don't increment born counter (for revival) */
 #define MM_IGNOREWATER	  0x80	/* ignore water when positioning */
+#define MM_ADJACENTOK	  0x100 /* its acceptable to use adjacent coordinates */
 
 /* flags for special ggetobj status returns */
 #define ALL_FINISHED	  0x01  /* called routine already finished the job */

src/makemon.c

@@ -790,9 +790,18 @@ register int	mmflags;
 			return((struct monst *)0);
 	}
 
-	/* if a monster already exists at the position, return */
-	if(MON_AT(x, y))
-		return((struct monst *) 0);
+	/* Does monster already exist at the position? */
+	if(MON_AT(x, y)) {
+		if ((mmflags & MM_ADJACENTOK) != 0) {
+			coord bypos;
+			if(enexto_core(&bypos, x, y, ptr, gpflags)) {
+				x = bypos.x;
+				y = bypos.y;
+			} else
+				return((struct monst *) 0);
+		} else 
+			return((struct monst *) 0);
+	}
 
 	if(ptr){
 		mndx = monsndx(ptr);