Downloadables should accept 'display', 'quality', 'resolution', 'frame' (it's job of implementation to  honour or not them). Resize image produced from Web Page to Image conversion.

git-svn-id: https://svn.erp5.org/repos/public/erp5/trunk@43335 20353a03-c40f-0410-a6d1-a30d3c3de9de