Added Update method to GraphNode

graph.go

@@ -158,6 +158,7 @@ type GraphNode interface {
   RegisterChannel(listener chan GraphSignal)
   UnregisterChannel(listener chan GraphSignal)
   UpdateChannel() chan GraphSignal
+  Update(signal GraphSignal)
 }
 
 func NewBaseNode(name string, description string, id string) BaseNode {
@@ -183,6 +184,10 @@ type BaseNode struct {
   listeners map[chan GraphSignal]chan GraphSignal
 }
 
+func (node * BaseNode) Update(signal GraphSignal) {
+  node.signal <- signal
+}
+
 func (node * BaseNode) Name() string {
   return node.name
 }