ENH: ad-hoc patch of newer jquery.dataTables to autfocus on search box

Picked up from cb3d8d932ab3f38fcc129db671809e5f3aceb0d5 commit within datalad codebase
which is present within older version of dataTables.  With this visitors immediately
focus on search box and can start searching!

assets/js/jquery.dataTables-1.10.21.js

@@ -4179,7 +4179,7 @@
 		var language = settings.oLanguage;
 		var previousSearch = settings.oPreviousSearch;
 		var features = settings.aanFeatures;
-		var input = '<input type="search" class="'+classes.sFilterInput+'"/>';
+        var input = '<input type="search" class="'+classes.sFilterInput+'" autofocus="autofocus"/>';
 
 		var str = language.sSearch;
 		str = str.match(/_INPUT_/) ?