xF1 Add-on [rellect] Last Seen Policy 1.0.7

This addons allows you to control which usergroups (or individual users) are allowed to hide their own online status and current activity.

In additional, inspired by WhatsApp, you can choose that members who hide their online status would not be able to see the online status of other members.

Permissions:

1. Can hide online status
2. Can hide current activity
3. Must share own online status to see others' status
4. Must share own current activity to see others' activity

Note: user with the permission to bypass privacy will always be able to see online status and current activity of others.

Note: online and visible staff members are excluded and always visible despite user's permissions. This is a design decision. Staff members who choose to be visible most likely want users to know when they are online.