Merge pull request #1062 from bigmihail/patch-1

Use $.prop() to get "multiple" attribute

select2.js

@@ -2873,7 +2873,7 @@ the specific language governing permissions and limitations under the Apache Lic
                 opts.element = $(this);
 
                 if (opts.element.get(0).tagName.toLowerCase() === "select") {
-                    multiple = opts.element.attr("multiple");
+                    multiple = opts.element.prop("multiple");
                 } else {
                     multiple = opts.multiple || false;
                     if ("tags" in opts) {opts.multiple = multiple = true;}