This commit adds some documentation for features recently added to SelectMenu
and TagsList components during the saas-16.3 development. A screenshot has
been provided to the advances use case of the SelectMenu, with a customization
of the bottom area of the dropdown, to create display a button allowing the
creation of items.
closesodoo/documentation#4468
Signed-off-by: Antoine Vandevenne (anv) <anv@odoo.com>
