Prevent default when opening a link in a new window. Fixes Swagger page opening twice.

Signed-off-by: Eric Riggs <ericriggs42@gmail.com>

mayan/apps/appearance/static/appearance/js/mayan_app.js

@@ -157,6 +157,7 @@ App.prototype.setupAutoSubmit = function () {
 
 App.prototype.setupNewWindowAnchor = function () {
     $('a.new_window').click(function (event) {
+        event.preventDefault();
         var newWindow = window.open($(this).attr('href'), '_blank');
         newWindow.focus();
     });