[P3] Sendmail Enhancements

• Project began in 1997/98 with Sendmail V8.8.8; current Sendmail-8.10.0 has made changes with regards to LDAP
• Three sample uses of LDAP + Sendmail are implemented:
  • recognize ``dotted'' userids as special ``local'' users via LDAP
  • recognize .mlst mailbox suffixes as special ``local'' mailing lists via MAIL500
  • treat unresolved ``local'' userids as ``local'' via LDAP