title: Shared angular modules not landing in webpack common chunk
body: <p>I have a lot of angular modules that are reused in the entire application, e.g.</p>
  <ul>
  <li>I18nModule</li>
  <li>StringInputModule</li>
  <li>...</li>
  </ul>
  <p>After building the app via angular CLI and inspecting the bundle with webpack bundle analyzer, these shared modules pop up in different modules that include them. Is there a way to force them into the <code>common</code> chunk instead? Or what are possible mistakes that can result into this behaviour of code duplication instead of detecting that it is indeed a shared module.</p>
  <p>To clarify: the common chunk exists, but only a handfull of ~ 50 shared modules are actually bundled within that chunk. The rest is either duplicated across different feature chunks or a lot of them are within the first feature page module.</p>
  <p>AoT is enabled, so is the <code>commonChunk</code> option (<a href="https://angular.io/cli/build" rel="nofollow noreferrer">https://angular.io/cli/build</a>)</p>