productivity/taskd

new update-plist found that:
Warning: taskd-1.1.0p2 defines @newgroup _taskd:734 (no entry in user db)
Warning: taskd-1.1.0p2 defines @newuser _taskd:732:734:daemon:Taskwarrior Sync Server:/var/taskd:/sbin/nologin (no entry in user db)

and indeed, taskd did not reserve any entry in user.list.

Apparently, 734 used to be icingacmd


I think it should be okay to reuse the id, but it should be registered in
user.list to avoid confusion...