refactor: move routing interfaces into their own files

src/PepperDash.Essentials.Core/Routing/IRouting.cs

@@ -0,0 +1,21 @@
+using System;
+using System.Collections.Generic;
+
+namespace PepperDash.Essentials.Core
+{
+    /// <summary>
+    /// Defines a midpoint device as have internal routing.  Any devices in the middle of the
+    /// signal chain, that do switching, must implement this for routing to work otherwise
+    /// the routing algorithm will treat the IRoutingInputsOutputs device as a passthrough
+    /// device.
+    /// </summary>
+    public interface IRouting : IRoutingInputsOutputs
+	{
+		void ExecuteSwitch(object inputSelector, object outputSelector, eRoutingSignalType signalType);        
+    }    
+
+    /*public interface IRouting<TInputSelector,TOutputSelector> : IRoutingInputsOutputs
+    {
+        void ExecuteSwitch(TInputSelector inputSelector, TOutputSelector outputSelector, eRoutingSignalType signalType);
+    }*/
+}