Rewrite structure : Enumerations
Code improvement for instancing enumerations.

Enumerations are called directly from the XML files in Forms, Filters, and Front Layout Filters (Menu items)
A new 'Enumeration' field has been created.
A new dedicated Helper is used for the static values. It is forkable, flexible, and optimized.
The caller view and the templates has been simplified.


To get a static list :
XxxxHelperEnum::_('enum_name');