Enums for features that change the layout version.
   * <br><br>
   * To add a new layout version:
   * <ul>
   * <li>Define a new enum constant with a short enum name, the new layout version 
   * and description of the added feature.</li>
Enums for features that change the layout version.
   * <br><br>
   * To add a new layout version:
   * <ul>
   * <li>Define a new enum constant with a short enum name, the new layout version 
   * and description of the added feature.</li> | DataNodeLayoutVersion.java