title: Remove all lines without an @ character in Notepad++
body: <p>I have a list like:</p>
  
  <pre><code>asd@asd
  abcdefgh
  abcde@fgh
  ijklmnop
  </code></pre>
  
  <p>I want to remove all lines without the symbol <code>@</code>. The result should be:</p>
  
  <pre><code> asd@asd
   abcde@fgh
  </code></pre>
  
  <p>Can this be done in Notepad++, and if so, how?</p>