Add users table and fix lots of bugs
Use autoload - partially done
Add wrapper.php, which all ajax traffic goes through
Move included files to lib/. Require PHP 5.3

1. addText: check duplicate titles
2. alternate: move posting rate to running state in tables.php
3. index: get expiry and basic data from users.php instead of at login
4. use __callStatic in fb and db, thus require php 5.3
5. sql: return affected rows for INSERT and UPDATE statements
6. Add the 'disabled' status for users. This indicates the account is
   locked permanently.
7. Fix lots of bugs