[IMP] Several UX improvements from saas6 version

calendar : When you create an event (for example from a job interview), you should be set as an attendee.
crm : Lead/opportunity : Bounce should be read only
hr_recruitment : 'Create Employee' should be an action button, instead of a link in the form
website_sale : SO report typo invoicing address instead of invoice address
website : remove Unpublish on the dropdown
website_sale : if accessory product is a non published product : do not show it on the ecommerce (avoid 403 error)