WordPress Bootstrap Pagination

/*
 * custom pagination with bootstrap .pagination class
 * source: http://www.ordinarycoder.com/paginate_links-class-ul-li-bootstrap/
 */
function david_post_pagination($echo = true)
{
    global $wp_query;

    $big = 999999999; // need an unlikely integer

    $pages = paginate_links(array(
            'base' => str_replace($big, '%#%', esc_url(get_pagenum_link($big))),
            'format' => '?paged=%#%',
            'current' => max(1, get_query_var('paged')),
            'total' => $wp_query->max_num_pages,
            'type'  => 'array',
            'prev_next'   => true,
            'prev_text'    => '<i class="fa fa-angle-left" aria-hidden="true"></i>',
            'next_text'    => '<i class="fa fa-angle-right" aria-hidden="true"></i>',
        ));

    if (is_array($pages)) {
        $paged = ( get_query_var('paged') == 0 ) ? 1 : get_query_var('paged');

        $pagination = '<ul class="pagination">';

        foreach ($pages as $page) {
            $pagination .= "<li>$page</li>";
        }

        $pagination .= '</ul>';

        if ($echo) {
            echo $pagination;
        } else {
            return $pagination;
        }
    }
}