title: Could not find module "@angular-devkit/build-angular" after npm install
body: <p>After running <code>npm install</code> then <code>npm update</code> I got this error when using <code>ng serve</code>:</p>
  
  <pre><code>Could not find module "@angular-devkit/build-angular" from "C:\\Users\\Matt\\Coding\\chart".
  Error: Could not find module "@angular-devkit/build-angular" from "C:\\Users\\Matt\\Coding\\chart".
  </code></pre>
  
  <p>Then checking the angular version, build-angular is there.</p>
  
  <pre><code>ng version
  </code></pre>
  
  <p>--</p>
  
  <pre><code>Package                            Version
  ------------------------------------------------------------
  @angular-devkit/architect          0.11.0 (cli-only)
  @angular-devkit/build-angular      &lt;error&gt;
  @angular-devkit/build-ng-packagr   &lt;error&gt;
  @angular-devkit/core               7.1.0 (cli-only)
  @angular-devkit/schematics         7.1.0 (cli-only)
  @schematics/angular                7.1.0 (cli-only)
  @schematics/update                 0.11.0 (cli-only)
  ng-packagr                         &lt;error&gt;
  rxjs                               6.3.3 (cli-only)
  typescript                         3.1.6 (cli-only)
  </code></pre>