[FIX] crm: set the oldname of field crm.lead.medium_id
[FIX] website_crm: contactus: do not polute lead creation values
[FIX] http.py: log 400 errors
[IMP] website_blog: Add menu, form view and tree view to manage tags.
[FIX] website_sale: apply reduction code

The line being deleted in this revision looks to have been useful when it was introduced in this commit:
36fc910

As the sale order was updated right away through the update_pricelist method
But since this rev. 22f4c31, the sale order is updated later, and reset the sale_order_code_pricelist_id value in the session right after setting it prevent to apply the pricelist of the promotional code...
[FIX] google_calendar: update tuto to create credential for google Calendar API. Google changes suddenly the process. Before that was optional, now without it, customers have an error 400 redirect_uri_mismatch