public PlanStaff CreateNewPlanStaff(Department department)
{
PlanStaff result = new PlanStaff();
result.Department = department;
result.Category = NullCategory.Instance;
result.Post = NullPost.Instance;
result.Prikaz = NullPrikaz.Instance;
PlanStaffs.InsertOnSubmit(result);
return result;
}