Use response.Text in Resource's handler

resource.go

@@ -36,9 +36,7 @@ func (resource *Resource) Handle(path string, w http.ResponseWriter, req *http.R
 
 	// Error out on bad IDs which contains /es
 	if x := strings.Index(subpath, "/"); x != -1 {
-		w.Header().Set("Content-Type", "text/plain; charset=utf-8")
-		w.WriteHeader(400)
-		w.Write([]byte("Invalid ID: " + subpath))
+		response.Text(w, 400, "Invalid ID: "+subpath)
 		return true
 	}