Users may remain as on-the-phone when the plugin is removed
1. User1 logs in
2. User2 logs in (should have User1 in his roster)
3. User1 starts a phone conversation with someone
4. User2 should see User1 as on-the-phone
5. Remove the asterisk plugin
6. User2 should see User1 available (no longer on-the-phone)
Step 6 is failing. The plugin needs to revert presences to previous state before having the phone call when it is being removed.