Create a marketplace package for resources-compat

This package contains all the UI files we've removed (xhtml, js, img, icons) from a previous LTS to the newest.
It needs to be packaged and downloadable from the Marketplace to not break customers application if they still use one of these resources, giving them the time to update their resources when they have time for it.

The nuxeo-resources-compat addon is emptied after each LTS release.