title: @objc error when migrated to Swift 2
body: <p>I had a <code>Swift</code> class declared like this:</p>
  
  <pre><code>@objc class MyHelper {
   // class code
  }
  </code></pre>
  
  <p>I had to do this to access such class from <code>Objective-C</code> classes, since I'm mixing languages in my project. Now that I upgraded to <code>Xcode 7</code>, I get this error:</p>
  
  <blockquote>
    <p>Only classes that inherit from NSObject can be declared @objc</p>
  </blockquote>
  
  <p>And such class is not known by my <code>Objective-C</code> classes anymore. I guess that then I should inherit my <code>Swift</code> class from <code>NSObject</code>, will that have any impact in the way the app was working?</p>
  
  <p>Thanks</p>