Added missing letters to graphite datasource nested query interpolation, #1294

src/app/features/graphite/datasource.js

@@ -232,7 +232,10 @@ function (angular, _, $, config, kbn, moment) {
       '#A', '#B', '#C', '#D',
       '#E', '#F', '#G', '#H',
       '#I', '#J', '#K', '#L',
-      '#M', '#N', '#O'
+      '#M', '#N', '#O', '#P',
+      '#Q', '#R', '#S', '#T',
+      '#U', '#V', '#W', '#X',
+      '#Y', '#Z'
     ];
 
     GraphiteDatasource.prototype.buildGraphiteParams = function(options) {