title: No syntax highlighting with React Monaco Editor
body: <p>Just installed <a href="https://www.npmjs.com/package/react-monaco-editor" rel="noreferrer">React Monaco Editor</a> and seems to be functioning properly except there is no syntax highlighting. I'm trying to use "python" as the language but the font stays the same gray default colour:</p>
  
  <p><a href="https://i.stack.imgur.com/TOhLX.png" rel="noreferrer"><img src="https://i.stack.imgur.com/TOhLX.png" alt="enter image description here"></a></p>
  
  <p>Any ideas on how to correct the issue?</p>
  
  <p>Here is my Code.js where I'm running the Monaco Editor:</p>
  
  <pre><code>import React from "react";
  import MonacoEditor from "react-monaco-editor";
  
  class Code extends React.Component {
    constructor(props) {
      super(props);
      this.state = {
        code: 'print("Hello, World!")'
      };
    }
    editorDidMount(editor, monaco) {
      console.log("editorDidMount", editor);
      editor.focus();
    }
    onChange(newValue, e) {
      console.log("onChange", newValue, e);
    }
    render() {
      const code = this.state.code;
      const options = {
        selectOnLineNumbers: true,
        fontSize: 18,
        colorDecorators: true
      };
      return (
        &lt;MonacoEditor
          width="800"
          height="600"
          language="python"
          theme="vs-dark"
          value={code}
          options={options}
          onChange={this.onChange}
          editorDidMount={this.editorDidMount}
        /&gt;
      );
    }
  }
  
  export default Code;
  </code></pre>
  
  <p>Also I added this code to the top of webpack.config.js:</p>
  
  <pre><code>const path = require('path');
  const MonacoWebpackPlugin = require('monaco-editor-webpack-plugin');
  module.exports = {
    plugins: [
      new MonacoWebpackPlugin({
        // available options are documented at https://github.com/Microsoft/monaco-editor-webpack-plugin#options
        languages: ['python']
      })
    ]
  };
  
  const APP_DIR = path.resolve(__dirname, './src');
  const MONACO_DIR = path.resolve(__dirname, './node_modules/monaco-editor');
  
  module.exports = {
    test: /\.css$/,
    include: APP_DIR,
    use: [{
      loader: 'style-loader',
    }, {
      loader: 'css-loader',
      options: {
        modules: true,
        namedExport: true,
      },
    }],
  }, {
    test: /\.css$/,
    include: MONACO_DIR,
    use: ['style-loader', 'css-loader'],
  }
  </code></pre>