JavaScript version selector I used before. Saving for future :)

index.html

<script>
    (function () {
        $('select[name="ProductVersion"]').change(function (e) {
            var $this = $(this),
                desiredVersion = $this.val(),
                currentPath = document.location.pathname + document.location.search,
                currentPathWithoutVersion = currentPath.substring(currentPath.indexOf('/', 1) === -1 ? currentPath.length : currentPath.indexOf('/', 1), currentPath.length),
                targetLocation = '/' + desiredVersion + currentPathWithoutVersion;

            document.location = targetLocation;
        });
    }());
</script>