mausezahn: provide port option to configuration file

Specify the port for the CLI in /etc/netsniff-ng/mausezahn.conf like so:

$ grep port /etc/netsniff-ng/mausezahn.conf
port = 65000

$ mausezahn -V -x -l 127.0.0.1

Mausezahn 0.40 - (C) 2007-2010 by Herbert Haas - http://www.perihel.at/sec/mz/
Use at your own risk and responsibility!
-- Verbose mode --

...
Opening config file /etc/netsniff-ng/mausezahn.conf...
...
Mausezahn accepts incoming Telnet connections on 127.0.0.1:65000.

Signed-off-by: Jon Schipp <jonschipp@gmail.com>
[tklauser: Fixed whitespace issues for patch to apply cleanly]
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
man: mausezahn: document rest of available config file options

This documents two more configuration file options that can be used.
One, automops, is in the development phase (not compiled by default),
and the other one, management-only, is usable. It prevents a user from
using a network interface to pass data traffic with the intention that
the interface is used for machine managment (remote control).

$ cat /etc/netsniff-ng/mausezahn.conf
user = mzadmin
password = better-password
management-only = eth0
automops = /path/to/an/automops-file.xml

Signed-off-by: Jon Schipp <jonschipp@gmail.com>
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>