title: how to setup bootstrap 4 scss with react webpack
body: <p>i'm starting a new project using reactjs ES6 and webpack</p>
  
  <p>using <a href="https://github.com/kriasoft/react-static-boilerplate" rel="noreferrer">react-static-boilerplate starter</a> question is how can i import bootstrap4 into the build proccess ?</p>
  
  <p>i dont want to use the bootstrap.css generated file, instead i want webpack to build it for me so i can get to change its @variables and apply my theme etc.</p>
  
  <p>i started project by cloning boilerplate</p>
  
  <pre><code>&gt; git clone -o react-static-boilerplate -b master --single-branch \
        https://github.com/kriasoft/react-static-boilerplate.git MyApp
  &gt;cd MyApp &amp;&amp; npm install
  </code></pre>
  
  <ol start="2">
  <li><p>installed bootstrap using npm</p>
  
  <p>npm install bootstrap@4.0.0-alpha.3</p></li>
  </ol>
  
  <p>now if i required the main bootstrap file into my index.js it will load fine. but how can i include the sass files of bootsrap to start customizing it ?</p>