[tz] tz mailing list guidelines

[Paul Eggert]

Now's as good a time as any to say what guidelines are
used when discarding or blocking contributions to the tz
mailing list.

The tz mailing list discusses proposals for updates that
would improve the time zone code and data.  When
contributions to the mailing list, on balance, harm the
project more than help it, it is often advisable to
discard them.  Examples of abuse include (but are not
limited to) spamming, commercial advertising, personal
attacks, repetitive or out-of-scope topics,
disinformation, sock puppetry, block evasion, copyright
violations, and legal threats.

An abusive mailing list correspondent should be blocked,
with contributions discarded.  The length of the block
should depend on the severity of the offenses and the
estimated future likelihood that future contributions
would help more than harm.  Correspondents whose
contributions consist entirely of spam, for example,
should be blocked permanently right away.  Correspondents
who make significant useful contributions should be
treated more leniently: their first block should be for a
period of a day to a week; the second, a month to six
months; and later blocks, one year to permanent.