// Taken from:
// http://stackoverflow.com/questions/263965/how-can-i-convert-a-string-to-boolean-in-javascript
stringToBoolean = function(string) {
  switch(string.toLowerCase()){
    case "true": case "yes": case "1": return true;
    case "false": case "no": case "0": case null: return false;
    default: return Boolean(string);
  }
}