preferred master option will force an election every 5 minutes if the

preferred master option will force an election every 5 minutes if the
server isn't a preferred master, and DEBUG(0,(...)) this.

reason: if the os level etc parameters aren't working properly, then
a domain master browser samba server that _ought_ to be the local master
browser as well might not.

i'll modify smb.conf.5 man page etc to reflect this change.

lkcl