[ADD] port disable_openerp_online

In 7.0 is annon bar is added by https://github.com/odoo/odoo/blob/7.0/addons/mail/static/src/xml/announcement.xml 
In 8.0 added by https://github.com/odoo/odoo/blob/8.0/addons/mail/static/src/xml/announcement.xml