Graphite: added second optional parameter to averageSeriesWithWildcards, Closes #926

src/app/services/graphite/gfunc.js

@@ -155,7 +155,10 @@ function (_) {
   addFuncDef({
     name: 'averageSeriesWithWildcards',
     category: categories.Combine,
-    params: [{ name: "node", type: "int" }],
+    params: [
+      { name: "node", type: "int" },
+      { name: "node", type: "int", optional: true },
+    ],
     defaultParams: [3]
   });