mail-storage.h interface changes, affects pretty much everything. FETCH, SEARCH, SORT and THREAD handling were pretty much moved from lib-storage/ to imap/ so adding non-index storages would be much easier now. Also POP3 server can now be easily implemented with lib-storage. Not too well tested, and at least one major problem: partial fetching is _slow_.

#ifndef __IMAP_THREAD_H
#define __IMAP_THREAD_H

int imap_thread(struct client *client, const char *charset,
		struct mail_search_arg *args, enum mail_thread_type type);

#endif