erp5_xhtml_style: report error messages on clone as errors
The script Base_createCloneDocument was made to be user-friendly, reporting
nice errors instead of throwing when a problems is detected. These errors are
displayed using the portal_status_message parameter of Base_redirect, which
looks like a warning on XHTML-style, but appears green with RenderJS.
This commit adds an optional parameter portal_status_level to all calls to
Base_redirect which are actually errors, so that they also look like a
warning or error (orange background) on RenderJS. The behaviour in XHTML-style
says identical.
/cc @romain @vpelletier