The, mboxc, widget supplements the mbox widget. The mbox widget
returns the subject of the last e-mail in a mbox, while the mboxc
widget returns the count of total, old and new messages. Dealing with
potentially *HUGE* files is not easy, I tried to find some middle
ground for now, comments in the file discuss it in detail. Having the
LuaFileSystem lib would be nice, so we could do caching and avoid 90%
of the reads, but I didn't rely on external libraries to this point so
I'm not going to start now.