[FIX] website: not well-formed HTML
[FIX] website: convert non-standard HTML metatag to data attribute
[FIX] website: remove illegal HTML attribute
[FIX] website: remove illegal HTML attribute
[REF] website: shorter tag for charset
[FIX] website: SEO promote box
[FIX] website: SEO js
Merge pull request #200 from odoo-dev/saas-4-w3validation-rim

[FIX] website: DOM fixes according to W3C Validator