netatalk: bump version

Netatalk goes to version 3.0.
The startup script has changed too, there is now only one binary called
netatalk. No more afpd, cnid, ... at startup ! They are executed by netatalk.

All the config is done within /etc/afp.conf, look at :
http://netatalk.sourceforge.net/3.0/htmldocs/upgrade.html


for more info about the upgrade process.

[Peter: added --without-kerberos to disable kerberos detection]
Signed-off-by: Peter Korsgaard <jacmet@sunsite.dk>