jQuery UI modal dialog close on overlay click option.

closeOnOverlayClick.patch

diff --git a/ui/jquery.ui.dialog.js b/ui/jquery.ui.dialog.js
index c5bd42a..9512c10 100644
--- a/ui/jquery.ui.dialog.js
+++ b/ui/jquery.ui.dialog.js
@@ -26,6 +26,7 @@ $.widget( "ui.dialog", {
 		autoOpen: true,
 		buttons: [],
 		closeOnEscape: true,
+		closeOnOverlayClick: false,
 		closeText: "Close",
 		dialogClass: "",
 		draggable: true,
@@ -778,9 +779,15 @@ $.widget( "ui.dialog", {
 		this.overlay = $("<div>")
 			.addClass("ui-widget-overlay ui-front")
 			.appendTo( this._appendTo() );
-		this._on( this.overlay, {
+		var events = {
 			mousedown: "_keepFocus"
-		});
+		};
+		
+		if ( this.options.closeOnOverlayClick ) {
+			events.click = "close";
+		}
+		
+		this._on( this.overlay, events );
 		this.document.data( "ui-dialog-overlays",
 			(this.document.data( "ui-dialog-overlays" ) || 0) + 1 );
 	},