removed the old plugin manager

lib/plugins/extension/helper/extension.php

lib/plugins/plugin/admin.php

lib/plugins/plugin/classes/ap_delete.class.php

lib/plugins/plugin/classes/ap_download.class.php

lib/plugins/plugin/classes/ap_enable.class.php

lib/plugins/plugin/classes/ap_info.class.php

lib/plugins/plugin/classes/ap_manage.class.php

lib/plugins/plugin/classes/ap_update.class.php

lib/plugins/plugin/lang/af/lang.php

lib/plugins/plugin/lang/ar/admin_plugin.txt

lib/plugins/plugin/lang/ar/lang.php

lib/plugins/plugin/lang/bg/admin_plugin.txt

lib/plugins/plugin/lang/bg/lang.php

lib/plugins/plugin/lang/ca-valencia/admin_plugin.txt

lib/plugins/plugin/lang/ca-valencia/lang.php

lib/plugins/plugin/lang/ca/admin_plugin.txt

lib/plugins/plugin/lang/ca/lang.php

lib/plugins/plugin/lang/cs/admin_plugin.txt

lib/plugins/plugin/lang/cs/lang.php

lib/plugins/plugin/lang/da/admin_plugin.txt