Made some improvements to ACL system including: warning on setting Deny for Everyone on the entire site, added ACL_ALWAYS_ALLOW_ADMIN_EDIT_ACL, and changed behavior as noted in the docs so that Deny for Everyone is no longer able to be overridden
Added a copy of Firebug Lite for debugging purposes. License is uncertain but being treated as MPL. (If is is not MPL then it is under something more permissive that permits relicensing anyway)