[leafnode-list] Pattern for only_groups_pcre (Leafnode 1).

[Adam Funk]

For suppressing binary groups, I started with Matthias's suggestion

   only_groups_pcre = ^\w+(\.\w+(?<!binaries|binary))*$

from http://article.gmane.org/gmane.network.leafnode/2323 but noticed
that all the groups with "-" and "+" in the names disappeared, and
that I was still getting some binary groups with non-English names, so
I've arrived at this:

  only_groups_pcre = ^([\+\-\w]+)(\.[\-\w]+(?<!binaries|binary|mp3|warez|binares|binarios|binari))*$

Does that cover all the characters that can legitimately appear in
newsgroup names?  Any other comments or suggestions?