$modifyUserRoles

To modify user roles, you can add/remove/toggle roles in same time
op can be:
+ for add
- for remove
~ for toggle

Usage

$modifyUserRoles[User ID;[op]Role 1;[op]Role 2;....]

Example (add role 1 and remove role 2):

$modifyUserRoles[$authorID;+role 1;-role 2]