Log Message:
Update mail/maildrop to 2.0.1.  Changes from version 1.8.1 include:

* Use PCRE (http://www.pcre.org) for mattern matching.
+ Most visible change is a different syntax for subexpression matching,
  using (...).  MATCH2 becomes MATCH1, MATCH3 becomes MATCH2, etc...
+ "w" account option dropped.
+ During a transitional period, setting MAILDROP_OLD_REGEXP
  reverts to the old pattern matching engine.

* Do not autoreply to messages with an Auto-Submitted: header, unless
  it's contents are "no".  Add Auto-Submitted: auto-replied.