pgsql: Add reverse(bytea).

Add reverse(bytea).

This commit introduces a function for reversing the order of the
bytes in binary strings.

Bumps catversion.

Author: Aleksander Alekseev <aleksander@timescale.com>
Discussion: https://postgr.es/m/CAJ7c6TMe0QVRuNssUArbMi0bJJK32%2BzNA3at5m3osrBQ25MHuw%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/0697b23906adabccba41fa7bf19909eb98bdf0dd

Modified Files
--------------
doc/src/sgml/func.sgml                | 17 +++++++++++++++++
src/backend/utils/adt/varlena.c       | 21 +++++++++++++++++++++
src/include/catalog/catversion.h      |  2 +-
src/include/catalog/pg_proc.dat       |  3 +++
src/test/regress/expected/strings.out | 18 ++++++++++++++++++
src/test/regress/sql/strings.sql      |  4 ++++
6 files changed, 64 insertions(+), 1 deletion(-)