[FIX] re-introduce is_set and is_not_set operators in advanced search
[FIX] re-introduce is_set and is_not_set operators in advanced search


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