code: function validateEvent(event) {
  	if (typeof event !== 'object' || !event) throw new TypeError('event must be an Object');
  	if (typeof event.type !== 'string' || !event.type.length) throw new TypeError('event.type must be a non-empty String');
  	if (!event.aggregateId && !event.sagaId) throw new TypeError('either event.aggregateId or event.sagaId is required');
  	if (event.sagaId && typeof event.sagaVersion === 'undefined') throw new TypeError('event.sagaVersion is required, when event.sagaId is defined');
  }
docs: Validate event structure
  
  @param {IEvent} event