Examples: Update unpredictable_data.php
Examples: Update unpredictable_data.php

- Adds a 4th example, showing how to make an extensible "unpredictable
  data container" which you can easily re-use in your classes.

SteveJobzniak/LazyJsonMapper,SteveJobzniak/LazyJsonMapper,aitte2/LazyJsonMapper,aitte2/LazyJsonMapper