title: Type 'Error' does not conform to protocol 'RawRepresentable'
body: <p>Changing my playground code to Swift 3, Xcode suggested changing</p>
  
  <pre><code>enum Error: ErrorType {
      case NotFound
  }
  </code></pre>
  
  <p>to</p>
  
  <pre><code>enum Error: Error {
      case NotFound
  }
  </code></pre>
  
  <p>but now I get the title error and I don't know how to get the enum to conform to that protocol.</p>