title: Whats the best way in kotlin for an null object's toString() method to return an empty string instead of "null"
body: <p>According to the official kotlin documentation, the toString() call of a null object returns "null" <a href="https://kotlinlang.org/api/latest/jvm/stdlib/kotlin/to-string.html" rel="noreferrer">toString()</a></p>
  
  <p>I want, that toString() should return an empty string ("") instead. I implemented it with an extension function.</p>
  
  <pre><code>fun Any?.toEmptyStringIfNull() :String {
  if (this == null) {
      return ""
  } else {
      return toString()
  }
  </code></pre>
  
  <p>I am wondering if this could be achieved simpler/easier/cleaner and without calling the extension function everytime.</p>