Not sure how you guys want this to be implemented. Moving all options included in calendar to a new _calendar_ option in Datepicker? So you would call Datepicker like this?

````
mySelector.datepicker({
	appendTo: null,
	calendar: {
		dateFormat: { date: "short" },
		eachDay: $.noop,
		max: null,
		min: null,
		numberOfMonths: 1,
		showWeek: false
	},
	position: { ... },
	show: true,
	hide: true,

	// callbacks
	beforeOpen: null,
	close: null,
	open: null,
	select: null
});
````

In the current code I wanted to prevent the calendar widget to be aware of the datepicker specific options which would be the case when using something like this:

````
this.calendarInstance = this.calendar
	.calendar($.extend( this.options, {
		value: this._getParsedValue(),
		select: function( event ) {
			that.element.val( that.calendarInstance.value() );
			that.close();
			that._focusTrigger();
			that._trigger( "select", event );
		}
	})
	.calendar( "instance" );
````