TASKPRI priority [task_description]

* TASKPRI sets the priority of a task, it can be displayed using
  "SHOW T". The priority must be between -127 and 128 and should
  be within -50 and 20 to avoid system-hangups. Standard is 0 .
* task_description is same as described at  BREAK .
* With one argument TASKPRI sets the priority of this task.
* If task_description is given, TASKPRI sets the priority of the
  given task.
NOTE: I did not like to call this command CHANGETASKPRI, because
      this name is really too long.

eg.     taskpri 2       {This task will be preferred}
        taskpri -1 3    {affects CLI no. 3}
        taskpri 4 Workbench