Decorator for elements supporting mutlselect order

[frenchcomp]

New decorator for multiselect form elements to support ordering.

Centurion provides a mechanism to save the order in relation, and return it in front, but no provide element in form to allow user to order elements. This patch provides a new decorator for multiselect to allow this :

To use the multiselect with ordering

• Add a trait on your form to support decorator provided by Core

        class myForm
                extends Centurion_Form_Model_Abstract
                implements  Core_Traits_Decorators_Form_Model_Interface

• overload the method render and add these lines before calls to method render of parent : (because Centurion_Form_Model reset elements decorators).

        $this->getElement('myManyToManyRelation')->setDecorators(array(
                   array('Multiselect' => 'MultiselectOrder')
               )
           );

@Todo : add a system allows developer to defines new paths in Decorator PluginLoader in the configuration, and remove the trait Core_Traits_Decorators_Form_Model_Interface

[lchenay]

This pull request need refractoring. Trait is useless, scripts js inline in the view ...

[lchenay]

Close this pull request. We already have this feature in Centurion.