Bug#412537: exim.8.gz: mention exit status, etc.

[Dan Jacobson]

Package: exim4-base
Version: 4.63-15
Severity: wishlist
File: /usr/share/man/man8/exim.8.gz

Mention EXIT STATUS: when will exim4 return what value to the shell.

Mention that exim's "sendmail -t with no arguments" is not portable, and
what should one use if one wants it also to work on a postfix machine.

Mention how user not in the trusted user list, and hence not able to
use mailq, can get any idea of if there mail was actually sent or not
or stuck etc., yes, when they haven't got an error reply.

P.S., no way to list or reset these:
  Spool file is locked (another process is handling..)
one can merely stare at them in the logfiles.