Add optional web_m2x_options options

Functions for contacts of companies should be created in the Functions
Tab. Functions created straight in the Contact form will not end up in the
Functions Tab.

Does not change behaviour on systems without web_m2x_options

base_contact_function/res_partner_view.xml

@@ -357,6 +357,7 @@
                    string="Parent Organisation" />
             <field name="function_id"
                    readonly="False"
+                   options="{'create': false, 'create_edit': false}"
                    domain="[('id', 'in', parent.function_ids[0][2])]"
                    string="Function"/>
           </group>