HPUX and OSF/1 support; fix SMTP reply codes & multiple SMTP error

HPUX and OSF/1 support; fix SMTP reply codes & multiple SMTP error
problem; consider cache timeout non-permanent; be more graceful on OS
failures; log forward, alias, and userdb expansions on log level 10

SCCS-vsn: usr.sbin/sendmail/src/READ_ME 6.4
SCCS-vsn: usr.sbin/sendmail/src/recipient.c 6.7
SCCS-vsn: usr.sbin/sendmail/src/macro.c 6.4
SCCS-vsn: usr.sbin/sendmail/src/main.c 6.15
SCCS-vsn: usr.sbin/sendmail/src/envelope.c 6.7
SCCS-vsn: usr.sbin/sendmail/src/version.c 6.19
SCCS-vsn: usr.sbin/sendmail/src/daemon.c 6.5
SCCS-vsn: usr.sbin/sendmail/src/srvrsmtp.c 6.4
SCCS-vsn: usr.sbin/sendmail/src/deliver.c 6.15
SCCS-vsn: usr.sbin/sendmail/src/queue.c 6.10
SCCS-vsn: usr.sbin/sendmail/src/conf.c 6.14
SCCS-vsn: usr.sbin/sendmail/src/alias.c 6.8
SCCS-vsn: usr.sbin/sendmail/src/udb.c 6.5
SCCS-vsn: usr.sbin/sendmail/src/mci.c 6.3