Addthis Plugin Extension in folder named dt-addthis

dt-addthis.php

<?php
/**
 * DT AddThis Extension Plugin
 *
 * @package   DT_AddThis
 * @author    Travis Smith <t@wpsmith.net>
 * @license   GPL-2.0+
 * @copyright 2014 Travis Smith
 *
 * @wordpress-plugin
 * Plugin Name:       AddThis Social Bookmarking Widget - Daniels Trading Extension
 * Plugin URI:        http://www.wpsmith.net
 * Description:       Extends AddThis Social Bookmarking Widget
 * Version:           1.0.0
 * Author:            Travis Smith
 * Author URI:        http://www.wpsmith.net
 * Text Domain:       dt-addthis
 * Domain Path:       /languages
 * License:           GPL-2.0+
 * License URI:       http://www.gnu.org/licenses/gpl-2.0.txt
 */

add_action( 'update_option_active_sitewide_plugins', 'dtat_deactivate_self', 10, 2 );
add_action( 'update_option_active_plugins', 'dtat_deactivate_self', 10, 2 );
/**
 *  Deactivate ourself if Addthis is deactivated.
 */
function dtat_deactivate_self( $plugin, $network_deactivating ) {
	if ( !is_plugin_active( 'addthis/addthis_social_widget.php' ) ) {
		deactivate_plugins( 'dt-addthis/dt-addthis.php', true );
	}
}

add_filter( 'addthis_post_exclude', 'dtat_addthis_post_exclude_filter' );
/**
 * Remove AddThis from specific custom post types.
 * 
 * Remove AddThis from facts, offers, tips, webinars, videos, and testimonials.
 *
 * @param  bool $display
 * @return bool Return false if one of a specific CPT.
 */
function dtat_addthis_post_exclude_filter( $display ) {
	if ( in_array( get_post_type(), array( 'fact', 'offer', 'tip', 'webinar', 'video', 'testimonial', ) ) ) {
		$display = false;
	}

	return $display;
}