[ADD] note about non-standard fields in facets and facet values
[ADD] note about non-standard fields in facets and facet values

havt/openerp-web,havt/openerp-web,akretion/openerp-web,havt/openerp-web,akretion/openerp-web,havt/openerp-web,havt/openerp-web,akretion/openerp-web