Massive commit with various changes. Added user ranks system (no admin interface yet) and ability for users to have custom user titles. Made cron framework accept fractions of hours through floating-point intervals. Modifed ACL editor to use miniPrompt framework for close confirmation box. Made avatar system use a special page as opposed to fetching the files directly for caching reasons.

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.