[FIX] web: allow to bypass postprocess on image widget

- If a CDN is used, this might cause issues for images that need access
  rights to be display.

  This is due to the fact that users are not connected on their account
  under the CDN domain, which makes the CDN requests reject since it is
  not authorized to access to those resources.

addons/web/models/ir_qweb.py

@@ -65,6 +65,7 @@ class Image(models.AbstractModel):
         atts["alt"] = alt
         atts["data-zoom"] = src_zoom and u'1' or None
         atts["data-zoom-image"] = src_zoom
+        atts["data-no-post-process"] = options.get('data-no-post-process')
 
         atts = self.env['ir.qweb']._post_processing_att('img', atts, options.get('template_options'))