function togglePeople(master, className) {
  var people = document.getElementsByClassName(className);
  if (master.checked) {
    for (i = 0; i < people.length; i++) { people[i].checked = true; }
  } else {
    for (i = 0; i < people.length; i++) { people[i].checked = false; }
  }
}

function toggleMaster(checkbox, master) {
  master = $(master)
  if(!master) return
  if (master.checked && !checkbox.checked) {
    master.checked = false;
  }
}