dispatch: channel reuse fix (#1237)

* Add test for dispatch channel reuse

* Dispatcher - make chans bidirectional

* No need to to keep the type assertion separate from the Get()

* Unexport Pipe's channel and add getter

dispatch/dispatch_types.go

@@ -72,7 +72,7 @@ type Mux struct {
 // Pipe defines an outbound object to the desired routine
 type Pipe struct {
 	// Channel to get all our lovely information
-	C <-chan interface{}
+	c chan interface{}
 	// ID to tracked system
 	id uuid.UUID
 	// Reference to multiplexer