Revert to Node 11 until Travis has Node 12 support
Revert to Node 11 until Travis has Node 12 support

arshaw/fullcalendar,arshaw/fullcalendar,fullcalendar/fullcalendar,arshaw/fullcalendar,oleg-babintsev/fullcalendar,fullcalendar/fullcalendar,oleg-babintsev/fullcalendar,arshaw/fullcalendar,oleg-babintsev/fullcalendar,fullcalendar/fullcalendar,fullcalendar/fullcalendar