How to use Yii's RBAC (Role-Based Access Control) system?

@darrion.kuhn 

1. Define Roles: The first step is to define the roles that you will be using in your system. For example, you might have roles such as admin, manager, user, etc. Create these roles in your RBAC system.
2. Assign Permissions: Once you have defined your roles, you can start assigning permissions. Permissions define what actions and operations each role can perform. For example, an admin might have permission to create new users or delete existing ones.
3. Create Users and Assign Roles: The next step is to create users and assign them roles. Users can be assigned one or more roles, depending on their level of access. For example, a manager might have access to certain areas that a regular user does not.
4. Check Permissions: Once your RBAC roles, permissions, and users are set up, you can start checking permissions. You can do this by using Yii's built-in functions to check whether a user has a particular permission or role.
5. Modify and Update Roles: As your system grows and evolves, you may need to modify and update your RBAC roles and permissions. You can easily do this by adding or removing roles, updating permissions, or modifying user roles. Make sure to test your changes thoroughly to ensure that they work correctly.

Remember, RBAC is an essential security feature that ensures that users have access only to the areas of your application that they need. By following these steps, you can set up RBAC in Yii and create a secure, well-structured application.