[IMP] website_sale : Don't show shipping address when only services are into shopping cart.

Hello,
Hide the shipping address into website_sale module when cart has only service type products.

More Details:
Task : https://www.odoo.com/web#id=9420&view_type=form&model=project.task&menu_id=3942&action=327
Pad : https://pad.odoo.com/p/r.aJDvr5RhQPSR6xjV

Thanks
rsi-odoo
@jem-odoo 
Here we required ```Shipping & Billing``` String in flow bar in three cases.
1) There is no any order (```not website_sale_order```)
2) When cart in empty, (```not website_sale_order.website_order_line```), pop out the product (empty) in cart that time flow string is changed.
3) When cart has any product other than service type (```not website_sale_order.only_services```)
Thanks