saveToken = async (token, userId, expires, type, blacklisted = false) => {
  const tokenDoc = await Token.create({
    token,
    user: userId,
    expires: expires.toDate(),
    type,
    blacklisted,
  });
  return tokenDoc;
}
Save a token
@param {string} token
@param {ObjectId} userId
@param {Moment} expires
@param {string} type
@param {boolean} [blacklisted]
@returns {Promise<Token>}