build: include lodash in webpack build (#1500)

* build: include lodash in webpack build

test/localintegrationrunner.html

@@ -9,7 +9,6 @@
     <div id="mocha"></div>
     <script src="../node_modules/mocha/mocha.js"></script>
     <script src="hacks/phantomhacks.js"></script>
-    <script type="text/javascript" src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.20/lodash.min.js" integrity="sha512-90vH1Z83AJY9DmlWa8WkjkV79yfS2n2Oxhsi2dZbIv0nC4E6m5AbH8Nh156kkM7JePmqD6tcZsfad1ueoaovww==" crossorigin="anonymous"></script>
     <script src="../build/ripple-latest.js"></script>
     <script>
       if (window.initMochaPhantomJS) {

webpack.config.js

@@ -9,9 +9,6 @@ function getDefaultConfiguration() {
   cache: true,
   performance: { hints: false },
   stats: 'errors-only',
-  externals: [{
-    'lodash': '_'
-  }],
   entry: './dist/npm/index.js',
   output: {
     library: 'ripple',