Auto "Focus" when click on "dropdown-filter-dropdown" icon

[RrOoSsSsOo]

It isn't a real issue but a very usefull feature! With this code into .js is possible to obtain the desidered behaviour

From:

FilterMenu.prototype.initialize = function () {
    ...
    $trigger.click(function () {
        return $content.toggle();
    });
    ...

To:

FilterMenu.prototype.initialize = function () {
    ...
    $trigger.click(function () {
        $content.toggle();
        $menu.find("input[type=text]").focus();
        return;
    });
    ...

[chestercharles]

feel free to make a pull request :)