Added new filters to modify the more popup window title and adding custom HTML content above share buttons

[appscreo]

add_filter('essb_morepopup_title', function($title) {
    $title = 'Custom window title';
    return $title;
});

add_filter('essb_morepopup_message', function() {
    return '<p>This is custom <b>message</b> in the window </p>';
});