title: In TypeScript, how to augment a type declaration with submodules
body: <p>I have a library (here it's highcharts), that have some type definition defined in the package <code>@types/highcharts</code> .</p>
  
  <p>in my code I'm importing, for example, <code>import * as highchartsSolidGauge from 'highcharts/modules/solid-gauge.src.js';</code></p>
  
  <p>This file is not defined in the definition package.</p>
  
  <p>SO I get the following error:</p>
  
  <pre><code>Could not find a declaration file for module 'highcharts/modules/solid-gauge.src.js'. './front-end/node_modules/highcharts/modules/solid-gauge.src.js' implicitly has an 'any' type.
    If the 'highcharts' package actually exposes this module, consider sending a pull request to amend 'https://github.com/DefinitelyTyped/DefinitelyTyped/tree/master/types/highcharts`
  </code></pre>
  
  <p>Given that :
    - I don't want to copy/paste everything of <code>@types/highcharts</code>
    - I dont't want (if possible) to pass an option that would deactivate every check on modules</p>
  
  <p>Is there a way to make this compile without changing the package <code>@types/highcharts</code> ?</p>
  
  <p>Highcharts is only an example, the question is essentially: how to augment a type definition to declare a submodule </p>