Dynamic Creature/Go spawning

Port From (https://github.com/TrinityCore/TrinityCore/commit/03b125e6d1947258316c931499746696a95aded2)

Source/Game/Maps/GridNotifiers.cs

@@ -2010,6 +2010,31 @@ namespace Game.Maps
         bool _reqAlive;
     }
 
+    class AnyPlayerInPositionRangeCheck : ICheck<Player>
+    {
+        public AnyPlayerInPositionRangeCheck(Position pos, float range, bool reqAlive = true)
+        {
+            _pos = pos;
+            _range = range;
+            _reqAlive = reqAlive;
+        }
+
+        public bool Invoke(Player u)
+        {
+            if (_reqAlive && !u.IsAlive())
+                return false;
+
+            if (!u.IsWithinDist3d(_pos, _range))
+                return false;
+
+            return true;
+        }
+
+        Position _pos;
+        float _range;
+        bool _reqAlive;
+    }
+    
     class NearestPlayerInObjectRangeCheck : ICheck<Player>
     {
         public NearestPlayerInObjectRangeCheck(WorldObject obj, float range)