website_crm: contact form improvement
get argument are processed and set into input fields + hidden fields
save some datas from http headers
controller should save all the submitted vars
[FIX] website_crm: update post value and not values object
[IMP] website_crm: prefill form with query strig value
[MERGE] from trunk
[IMP] website_crm: contact form improvement
get argument are processed and set into input fields + hidden fields
save some datas from http headers
controller should save all the submitted vars
[FIX] sprurious widgetification and editability of icon elements

* tighten widget match: don't match elements with .fa which are also "view
  section" roots (~ editing hosts) as the classes themselves out not be
  editable and the result will thus be odd
* correspondingly, only associate the icon "change" button to instances of the
  ``icons`` widget, other elements bearing ``.fa`` are not editable and should
  be excluded.
[FIX] website#ir.http: do not postprocess arguments on non `website_enabled` endpoints