* added utf-8 markers to all .py files in plugins/{action,cache,callback}
* added utf-8 markers to all .py files in plugins/connection
* added utf-8 markers to all .py files in plugins/doc_fragments
* callback_type -> type.
* Mark authors as unknown.
* Add author field forgotten in #627.
* Fix author entries.
* Add author field forgotten in #127.
* Fix some types.