eventDrop
Triggered when dragging stops and the event has moved to a different day/time.
function( eventDropInfo ) { }
eventDropInfo is a plain object with the following properties:
| delta | 
       A Duration Object that represents the amount of time the event was moved by.  | 
|---|---|
| el | 
       The HTML element that was dragged.  | 
| event | 
       An Event Object that holds information about the event (date, title, etc) after the drop.  | 
| jsEvent | 
       The native JavaScript event with low-level information such as click coordinates.  | 
| newResource | 
       If the resource has changed, this is the Resource Object the event went to. If the resource has not changed, this will be undefined. For use with the resource plugins only.  | 
| oldEvent | 
       An Event Object that holds information about the event before the drop.  | 
| oldResource | 
       If the resource has changed, this is the Resource Object the event came from. If the resource has not changed, this will be undefined. For use with the resource plugins only.  | 
| revert | 
       A function that, if called, reverts the event’s start/end date to the values before the drag. This is useful if an ajax call should fail.  | 
| view | 
       The current View Object.  | 
eventDrop does not get called when an external event lands on the calendar. eventReceive is called instead.
Here is an example demonstrating most of these arguments:
var calendar = new Calendar(calendarEl, {
  events: [
    // events here
  ],
  editable: true,
  eventDrop: function(info) {
    alert(info.event.title + " was dropped on " + info.event.start.toISOString());
    if (!confirm("Are you sure about this change?")) {
      info.revert();
    }
  }
});
Resources
When an event has been newly dropped on a resource, the Event Object’s resources will be updated to reflect.