[FIX] website_sale: save the company in street and the street in street2.

The old behaviour was not better, because when we print the invoice, the order was ugly:
    Name
    Street
    Company name
    Country

Now we will have:
    Name
    Company name
    Street
    Country

This patch is not retro-compatible:
   Old partners will see the address in company name and vice-versa.
   Need to update view and switch street field and street2 field
[IMP] website_event: add mail subtypes

Add published and unpublised mail subtypes, to track events publication, and to be able to follow these subtypes