title: Realm, avoid to store some property
body: <p>I need to implement a protocol in my User model, which need to have some special properties. But I'd like to avoid them to be stored/persisted in Realm database.</p>
  
  <p>I didn't see in the documentation if there was a keyword for this. Did there is a trick to avoid saving some properties ?</p>
  
  <pre><code>public final class User: Object, Mappable, AvatarImageViewDataSource {
  
  dynamic var id: Int = 0
  dynamic var desc: String? = nil
  dynamic var email: String? = nil
  dynamic var firstName: String? = nil
  dynamic var lastName: String? = nil
  
  ...
  
  public var myPropertyIDontWantToSave: String? = nil // I don't want this to be stored
  </code></pre>