list_users outputs all users onto users.php, and can be slow

[Julian Lam]

The function list_users currently returns ALL users found with a specific user type. In the case of students, there may be hundreds using the cage system, which would lead to the users.php page slowing down in rendering all records, as they must be retrieved one at a time and output to the page.

Also, it leads to a heck of a lot of scrolling.

Solutions can be to limit the shown users to 30 (LIMIT 0, 30), and have a "next" button to show more...

Also, search by name would be nice as well, in addition to search by student number.