added a funtion to add a global (plugin) handler

add a function for registering "global" (plugin) handlers.

client.go

@@ -41,6 +41,7 @@ func NewClient(ctx context.Context, params RegistrationParams) *Client {
 		ctx:      ctx,
 		params:   params,
 		actions:  make(map[string]*Action),
+		handlers: make(map[string][]EventHandler),
 		done:     make(chan struct{}),
 	}
 }
@@ -204,6 +205,10 @@ func (client *Client) SendToPlugin(ctx context.Context, payload interface{}) err
 	return client.send(NewEvent(ctx, SendToPlugin, payload))
 }
 
+func (client *Client) RegisterHandler(eventName string, handler EventHandler) {
+	client.handlers[eventName] = append(client.handlers[eventName], handler)
+}
+
 func (client *Client) Close() error {
 	err := client.c.WriteMessage(websocket.CloseMessage, websocket.FormatCloseMessage(websocket.CloseNormalClosure, ""))
 	if err != nil {