first part of tip 76 -- multiple packages as subsites adds a subsite::package_keys function for listing subsites, and uses it instead of hard coding acs-subsite all over
Added elements subsite_node_id, subsite_url, vhost_subsite_url and vhost_package_url to allow includes and master templates to vhost aware server relative urls. Added subsite::get_url to allow functions to generate vhost aware absolute urls.