title: react-native: Command `run-android` unrecognized. Maybe caused by npm install
body: <p>Recently I started getting this issue, when I install a react-native package 
  (eg: <code>react-navigation</code>) into my project, a whole bunch of packages are been removed (including react, react-native i think). </p>
  
  <p>And then when i try to run command "<code>run-android</code>", it says it doesn't recognize. </p>
  
  <p>I recently updated to the latest <code>npm</code> and <code>react-native-cli</code>. Is it something wrong with "<code>npm install</code>"? or <code>react-native</code>?</p>
  
  <pre><code>node version: 8.1.2 &lt;br/&gt;
  react-native-cli: 2.0.1 &lt;br/&gt;
  react-native: 0.45.1 &lt;br/&gt;
  react-navigation: 1.0.0-beta.11
  </code></pre>
  
  <p>Below are the steps to re-create:</p>
  
  <blockquote>
    <ul>
    <li><p>Step 1 - Create project.
    <a href="https://i.stack.imgur.com/aNU0o.png" rel="noreferrer"><img src="https://i.stack.imgur.com/aNU0o.png" alt="enter image description here"></a></p></li>
    <li><p>Step 2 - Run the "run-android" command (This works).
    <a href="https://i.stack.imgur.com/zj2UW.png" rel="noreferrer"><img src="https://i.stack.imgur.com/zj2UW.png" alt="enter image description here"></a></p></li>
    <li><p>Step 3 - Install "react-native-navigation" into project.
    <a href="https://i.stack.imgur.com/Q95Gi.png" rel="noreferrer"><img src="https://i.stack.imgur.com/Q95Gi.png" alt="enter image description here"></a></p></li>
    </ul>
  </blockquote>
  
  <pre><code>Notice in the image above. Seems like all the other packages are removed from the project.&lt;br/&gt;&lt;br/&gt;
  </code></pre>
  
  <blockquote>
    <ul>
    <li>Step 4 - Try running "run-android" command again. (will fail, but used to work before)
    <a href="https://i.stack.imgur.com/cAJyH.png" rel="noreferrer"><img src="https://i.stack.imgur.com/cAJyH.png" alt="enter image description here"></a></li>
    </ul>
  </blockquote>
  
  <p>Any idea on what the issue is and any way to solve it?</p>