/**
  * Get the reverse diff for this diff
  *
  * @return PropelColumnDiff
  */
 public function getReverseDiff()
 {
     $diff = new self();
     // columns
     $diff->setFromColumn($this->getToColumn());
     $diff->setToColumn($this->getFromColumn());
     // properties
     $changedProperties = array();
     foreach ($this->getChangedProperties() as $name => $propertyChange) {
         $changedProperties[$name] = array_reverse($propertyChange);
     }
     $diff->setChangedProperties($changedProperties);
     return $diff;
 }