title: Libraries not working after implementing Webpack (SKD3)
body: <p>I am creating a Sankey diagram using <a href="https://github.com/fabriciorhs/skd3" rel="nofollow noreferrer">SKD3</a> . It works fine when i add the libraries the normal way ie:</p>
  
  <pre><code>&lt;script src="https://unpkg.com/d3@4.10.2/build/d3.min.js"&gt;&lt;/script&gt;
  &lt;script src="//rawgit.com/FabricioRHS/skd3/master/build/sk.d3.min.js"&gt;&lt;/script&gt;
  </code></pre>
  
  <p>After implementing Webpack, i have errors like 'i.createSankey is not a function'</p>
  
  <p>'createSankey' is from the SKD3 library which works fine without webpack</p>
  
  <p>i tried to disable uglyfying the js: <code>minimize: false</code> in the webpack.config.js file and then i get : 'skd3_build_sk_d3_js__WEBPACK_IMPORTED_MODULE_1__.createSankey is not a function'</p>
  
  <p>This is my simple index.js file:</p>
  
  <pre><code>import * as d3 from "d3";
  import * as sk from "skd3/build/sk.d3.js";
  (function() {
      console.log('hi');
      var configSankey = {
          margin: { top: 10, left: 10, right: 10, bottom: 10 },
          nodes: {
              dynamicSizeFontNode: {
                  enabled: true,
                  minSize: 14,
                  maxSize: 30
              },
              fontSize: 14, // if dynamicSizeFontNode not enabled
              draggableX: false, // default [ false ]
              draggableY: true, // default [ true ]
              colors: d3.scaleOrdinal(d3.schemeCategory10)
          },
          links: {
              formatValue: function(val) {
                 return d3.format(",.0f")(val) + ' TWh';
              },
              unit: 'TWh' // if not set formatValue function
          },
          tooltip: {
             infoDiv: true,  // if false display default tooltip
             labelSource: 'Input:',
             labelTarget: 'Output:'
          }
      }   
      var datajson = {nodes: [
       {id: 0, name: "Alice", color: "green"},
       {id: 1, name: "Bob", color: "yellow"},
       {id: 2, name: "Carol", color: "blue"}
      ],
      links: [
       {source: 0, target: 1, value: 1},
       {source: 1, target: 2, value: 1}
      ]};
      var objSankey = sk.createSankey('#sankey', configSankey, datajson);
  })();
  </code></pre>
  
  <p>Anyone has an idea on how to solve this? </p>
  
  <p>I'm new to webpack but i tried searching everywhere for the answer but i can't find it. Need help from you guys. Thanks alot!</p>