New release notes: SA-03.19, tcp_hostcache, compat4x.i386 updates,
nologin(8) C implementation, no more sysinstall(8) security profiles

Modified release notes: Dynamic /bin and /sbin only apply to non-ia64,
BIND 8.3.7 (+ MFC), add old version information to sendmail update
note.

Approved by: re (implicitly)