Added getAccessToken method to FBUser class
Fixed AppUser class bugs

- and improved functionality by not querying the database on every "get"
Changed constructors in FBUser and AppUser

- to use references
Changed check.php and check.tpl to use OOP

check.php now uses the created OOP classes.
Removed echo
Replaced getResult with getField

More intuitive, actually works.
Fixed last_check error

Error was caused by last check not being initialized.
Also changed it to use getField.
Fixed last check bug and reactivation bug

- last check wasn't being set properly
- new friends were being wrongly set to "reactivated"