/**
  * Inserts a user account field into the DB and returns the insert_id.
  * 
  * @param object $emailAddress (username)
  * @param object $password (in clear text)
  * @param object $displayName
  * @return 
  */
 private static function dbTask_insertUser($emailAddress, $password, $displayName)
 {
     self::_init();
     $passwordHash = phpPass::hashPassword($password);
     $stmt = self::$mysqli->prepare("INSERT INTO `users` SET `emailAddress`=?,`displayName`=?,`passwordHash`=?");
     /*
     Can be used for debugging:
     if ( false===$stmt ) die('prepare() failed: ' . htmlspecialchars(self::$mysqli->error));
     */
     $stmt->bind_param('sss', $emailAddress, $displayName, $passwordHash);
     $stmt->execute();
     $insertId = $stmt->insert_id;
     $stmt->close();
     return $insertId;
 }
 private static function init()
 {
     self::$passwordHash = new PasswordHash(8, false);
 }