Purpose
=======
On our saas, when users configure a mail server, they can't use anymore
the "odoo.com" configuration (which is stored in the odoo-bin argument).
To allow them to continue using the SMTP CLI configuration, we add a
new "smtp_authentication". When this authentication method is chosen,
all the "connection" fields of the mail server are ignored, and the
connection information are taken from the odoo-bin arguments. So they
can choose the from filter of this SMTP configuration, the priority...
Task-3061882
closesodoo/odoo#106297
Signed-off-by: Thibault Delavallee (tde) <tde@openerp.com>