MessageHandler = function MessageHandler(gladys, serviceId, axios) {
  this.gladys = gladys;
  this.serviceId = serviceId;
  this.axios = axios;
  this.bots = {};
  this.newMessageCb = eventFunctionWrapper(newMessage.bind(this));
}
@description Add ability to send/receive Nextcloud Talk message.
@param {object} gladys - Gladys instance.
@param {string} serviceId - UUID of the service in DB.
@param {object} axios - Axios library.
@example
const messageHandler = new MessageHandler(gladys, serviceId, axios);