* doxygen: fix comments
* fix whitespace
* rename mutt_emaillist_free() to _clear()
* drop unused maildir_update_tables()
* de-Context nntp_check_msgid()
* de-Context nntp_check_children()
* boolify imap_next_word()
* rename dreadful local
* email: shorten function names
* rename ParameterList variables
* unify private data free functions
* hash: pick some better variable names
* iwyu: tidy #includes