Log Message:
Upgrade mailsync to version 4.4.4.  Patch from Michael Pasternak.  Notable
changes include:
 * Check every fetch operation for success
 * documented the fact that mailsync is not really fit for concurrent
   mailbox access
 * extended loging
 * reengineering - clearer naming of variables (I hope)
                 - int msgno -> unsigned long msgno (as in c-client)
                 - functions and variables that return/contain only true/false
                   are now booleans
 * do not copy deleted mails
 * documented list mode
 * list mode can display contents of mailboxes
 * more docu
 * reordered code to make it more coherent (IMHO)
 * various functions (fetch_mail_ids, tdc_mail_open) had too many crucial
   side effects which made the code very hard to follow. Untangled that.
 * closing a stream before writing in it (c-client logic!) so that new
   messages are not marked as seen. That means, that mutt users should be
   happy(er?) now.
 * more explicit and consistent error messages, more sensible debug output
 * documented the code and renamed stuff so that it makes sense
 * messages-ids are sanitized and saved in RFC822 format only.
 * warnings about spaces in the message id are now optional, see the "-bd"
   option
 * fixed a bug that occured when files were copied over but could not be saved
   for some reason