[FIX] web: t-attf expects #{} or {{}} for variables

not just {}. Nevertheless, It somehow worked in Odoo 7.0 and saas-3.
[FIX] website: main layout - title more flexible for customization. (additionnal_)title was overwritted by website_meta_title or main_object.name
Merge branch '8.0' of https://github.com/odoo/odoo into 8.0-win32