rm heatmapgl from lib/index.js :

- 'heatmagl' is only available through custom bundling by
  require('plotly.js/lib/heatmapgl');

Author: etpinard

lib/heatmapgl.js

@@ -0,0 +1,9 @@
+/**
+* Copyright 2012-2016, Plotly, Inc.
+* All rights reserved.
+*
+* This source code is licensed under the MIT license found in the
+* LICENSE file in the root directory of this source tree.
+*/
+
+module.exports = require('../src/traces/heatmapgl');

lib/index.js

@@ -30,8 +30,7 @@ Core.register([
     require('./scattergeo'),
     require('./choropleth'),
     require('./scattergl'),
-    require('./scatterternary'),
-    require('../src/traces/heatmapgl')
+    require('./scatterternary')
 ]);
 
 module.exports = Core;