pgsql: Rename pg_validatebackup to pg_verifybackup.

Rename pg_validatebackup to pg_verifybackup.

Also, use "verify" rather than "validate" to refer to the process
being undertaken here. Per discussion, that is a more appropriate
term.

Discussion: https://www.postgresql.org/message-id/172c9d9b-1d0a-1b94-1456-376b1e017322@2ndquadrant.com
Discussion: http://postgr.es/m/CA+TgmobLgMh6p8FmLbj_rv9Uhd7tPrLnAyLgGd2SoSj=qD-bVg@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/dbc60c5593f26dc777a3be032bff4fb4eab1ddd1

Modified Files
--------------
doc/src/sgml/ref/allfiles.sgml | 2 +-
doc/src/sgml/ref/pg_basebackup.sgml | 4 +-
...pg_validatebackup.sgml => pg_verifybackup.sgml} | 56 ++++++-------
doc/src/sgml/reference.sgml | 2 +-
src/bin/Makefile | 2 +-
src/bin/pg_validatebackup/.gitignore | 2 -
src/bin/pg_verifybackup/.gitignore | 2 +
.../Makefile | 18 ++--
.../parse_manifest.c | 4 +-
.../parse_manifest.h | 2 +-
.../pg_verifybackup.c} | 96 +++++++++++-----------
.../t/001_basic.pl | 18 ++--
.../t/002_algorithm.pl | 10 +--
.../t/003_corruption.pl | 14 ++--
.../t/004_options.pl | 28 +++----
.../t/005_bad_manifest.pl | 4 +-
.../t/006_encoding.pl | 6 +-
.../t/007_wal.pl | 14 ++--
18 files changed, 142 insertions(+), 142 deletions(-)