'RELENG_4_0_0_RELEASE'.

This commit was manufactured to restore the state of the 4.0-RELEASE image.
Releases prior to 5.3-RELEASE are omitting the secure/ and crypto/ subdirs.

- Get rid of a lot of the static variables which were shared by
  many routines and programs in the suite.
- Create an abstract interface to the printcap database, so that
  other retrieval and iteration mechanisms could be developed
  (e.g., YP, Hesiod, or automatic retrieval from a trusted server).
- Give each capability a human-readable name in addition to the historic
  two-character one.
- Otherwise generally clean up a lot of dark corners.  Many still remain.
- When submitting jobs, use the official login name record (from getlogin())
  if there is one, rather than reverse-mapping the uid.

More to come...

The removed files are no longer needed, they are actually labelled as
``Use only if you are not 4.4BSD''.  (Yeah, the ol' crufty printcap.c
is really gone!)

Properly declare all external objects in files ending in .h, as
opposed to embed them into files ending in .c.