Add support for registering jQuery as an AMD module. Only does so if the AMD loader indicates it has special allowances for multiple versions of jQuery being loaded in a page.

src/core.js

@@ -930,6 +930,20 @@ function doScrollCheck() {
 	jQuery.ready();
 }
 
+// Expose jQuery as an AMD module, but only for AMD loaders that
+// understand the issues with loading multiple versions of jQuery
+// in a page that all might call define(). The loader will indicate
+// they have special allowances for multiple jQuery versions by
+// specifying define.amd.jQuery = true. Register as a named module,
+// since jQuery can be concatenated with other files that may use define,
+// but not use a proper concatenation script that understands anonymous
+// AMD modules. A named AMD is safest and most robust way to register.
+// Lowercase jquery is used because AMD module names are derived from
+// file names, and jQuery is normally delivered in a lowercase file name.
+if ( typeof define === "function" && define.amd && define.amd.jQuery ) {
+	define( "jquery", [], function () { return jQuery; } );
+}
+
 // Expose jQuery to the global object
 return jQuery;