redo egg drop timer, tidy code

chicken.lua

@@ -60,10 +60,16 @@ mobs:register_mob("mobs_animal:chicken", {
 		mobs:capture_mob(self, clicker, 30, 50, 80, false, nil)
 	end,
 
-	do_custom = function(self)
+	do_custom = function(self, dtime)
+
+		self.egg_timer = (self.egg_timer or 0) + dtime
+		if self.egg_timer < 10 then
+			return
+		end
+		self.egg_timer = 0
 
 		if self.child
-		or math.random(1, 5000) > 1 then
+		or math.random(1, 100) > 1 then
 			return
 		end
 
@@ -127,9 +133,9 @@ mobs:register_arrow("mobs_animal:egg_entity", {
 
 	hit_node = function(self, pos, node)
 
-		local num = math.random(1, 10)
-
-		if num == 1 then
+		if math.random(1, 10) > 1 then
+			return
+		end
 
 		pos.y = pos.y + 1
 
@@ -164,7 +170,6 @@ mobs:register_arrow("mobs_animal:egg_entity", {
 		ent2.tamed = true
 		ent2.owner = self.playername
 	end
-	end
 })