[FIX] product: don't display 'create and edit' option on many2many_tag to create variant on product_template. The quick create is confusing for users
[IMP] doc/howtos/backend: fix condition in workflow
Merge pull request #1970 from odoo-dev/8.0-fix-dont-display-edit-product-many2many-chm

[FIX] product: don't display 'create and edit' option on many2many_tag
[FIX] website.layout hreflangs

- First line is not correct due to url_for() refactoring's leftover
- href's should be full urls with domain name
- Use short language for hreflang if possible
[FIX] Missing part of the revision 5f6fc473