Fixed Rig Manager Update not executing correctly when collection is modified during its execution. (#40)

CHANGELOG.md

 
 #### Added
 
+#### Fixed
+
+* Fixed Rig Manager Update not executing correctly when collection is modified during its execution.
+
 ## 2020.2.3
 
 #### Added

Runtime/Ingredients/Rigs/RigManager.cs

             var priorities = dict.Keys.OrderBy(i => i);
             foreach(int priority in priorities)
             {
-                foreach(var rig in dict[priority])
+                if(dict.ContainsKey(priority))
-                    rig.UpdateRig(deltaTime);
+                    foreach (var rig in dict[priority].ToArray())
+                    {
+                        rig.UpdateRig(deltaTime);
+                    }
+
             }
         }