pgsql: Remove contrib/chkpass

Remove contrib/chkpass

The recent addition of a test suite for this module revealed a few
problems. It uses a crypt() method that is no longer considered secure
and doesn't work anymore on some platforms. Using a volatile input
function violates internal sanity check assumptions and leads to
failures on the build farm.

So this module is neither a usable security tool nor a good example for
an extension. No one wanted to argue for keeping or improving it, so
remove it.

Discussion: https://www.postgresql.org/message-id/5645b0d7-cc40-6ab5-c553-292a91091ee7%402ndquadrant.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5d3cad564729f64d972c5c803ff34f0eb40bfd0c

Modified Files
--------------
contrib/Makefile | 1 -
contrib/chkpass/.gitignore | 4 -
contrib/chkpass/Makefile | 23 ----
contrib/chkpass/chkpass--1.0.sql | 70 -----------
contrib/chkpass/chkpass--unpackaged--1.0.sql | 13 --
contrib/chkpass/chkpass.c | 175 ---------------------------
contrib/chkpass/chkpass.control | 5 -
contrib/chkpass/expected/chkpass.out | 18 ---
contrib/chkpass/sql/chkpass.sql | 7 --
doc/src/sgml/chkpass.sgml | 95 ---------------
doc/src/sgml/contrib.sgml | 1 -
doc/src/sgml/filelist.sgml | 1 -
12 files changed, 413 deletions(-)