title: The authenticity of host 'github.com (192.30.252.128)' can't be established
body: <p>I am trying to use</p>
  <pre><code>sudo npm install
  </code></pre>
  <p>to install all my dependencies for an application written in nodejs. My OS is Ubuntu 13.04</p>
  <p>However, I keep getting this warning:</p>
  <pre><code>The authenticity of host 'github.com (192.30.252.131)' can't be established.
  RSA key fingerprint is 16:27:ac:a5:76:28:1d:52:13:1a:21:2d:bz:1d:66:a8.
  Are you sure you want to continue connecting (yes/no)?
  </code></pre>
  <p>Has anyone encountered this warning before? Is it possible to authenticate and store the fingerprint locally? So I won't need to authenticate again when I enter sudo npm install another time.</p>
  <p>Right now, I am unable to enter anything, not even &quot;yes&quot;. My terminal just gets stuck, i have to press <kbd>Ctrl</kbd>+<kbd>C</kbd> to terminate.</p>