add a optional limit on number of npcs per scene default = 40

bin/OpenSim.ini.example

@@ -1208,6 +1208,11 @@
     ;# {Enabled} {} {Enable Non Player Character (NPC) facilities} {true false} false
     ; Enabled = false
 
+    ;; max number of NPCs per scene default: 40
+    ;; set to a negative value to allow any number
+    ;; note that a NPC is almost as heavy as a normal avatar, so you should limit them
+    ;; MaxNumberNPCsPerScene = 40
+
     ;; several options to control NPCs creation
 
     ;# {AllowNotOwned} {} {allow NPCs to be created not Owned} {true false} true