Got ACL scope logic working again and began enforcing it. Breaking API change: assigning page title with $template->tpl_strings['PAGE_NAME'] will no longer work, use $template->assign_vars(). Workaround may be added later. Test for assign_vars method if compatibility needed. Added namespace processor API (non-breaking change). Several other things tweaked around as well.

These icons are from the Flygo icon set, which is based on icons from the Tango
Desktop Project. They are released under the GNU General Public License.