* Another use of getAll.
* If the optional third boolean parameter $isComplete is set to "true",
* every object is completely instantiated, including inheritence and agregation.
* Note : "order" does not work on fields of base classes in case of inheritence (when $isComplete is true). Will be fixed.
// one line to get an array of complete objects...
$persistence = new Persistence();
$products = $persistence->getAll("Wine", null, true);