Update 2

- Moved login form to login.php
- Added validation to login.php
- Added registration to login.php
- Ability to add events in addevent.php
- Added validation to addevent.php
- Added 'userid' field to 'events' table
- Added some functions to help with adding events
- Now using PHP code to hide/show modules instead of CSS ":target" rule
- Added ability to jump to target days
- Added 'admin' variable to $_SESSION