Moved the polling of data from the webgui to its own dedicated poller.

This should simplify testing of webgui.

cmd/invertergui/main.go

@@ -44,7 +44,8 @@ func main() {
 	flag.Parse()
 
 	source := datasource.NewJSONSource(*url)
-	gui := webgui.NewWebGui(source, 10*time.Second, 100)
+	poller := datasource.NewDataPoller(source, 10*time.Second)
+	gui := webgui.NewWebGui(poller, 100)
 	http.Handle("/", gui)
 	http.Handle("/munin", http.HandlerFunc(gui.ServeMuninHTTP))
 	http.Handle("/muninconfig", http.HandlerFunc(gui.ServeMuninConfigHTTP))