pgsql: pg_createsubscriber: Rename option --remove to --clean

pg_createsubscriber: Rename option --remove to --clean

After discussion, the name --remove was suboptimally chosen. --clean
has more precedent in other PostgreSQL tools.

Reviewed-by: Hayato Kuroda (Fujitsu) <kuroda.hayato@fujitsu.com>
Discussion: /messages/by-id/84be7ff3-2763-4c0f-ac1e-ca9862077f41@eisentraut.org

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/60dda7bbc45f30e2ba50ecf20dfb9d944a589a38

Modified Files
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doc/src/sgml/ref/pg_createsubscriber.sgml | 59 +++++++++++-----------
src/bin/pg_basebackup/pg_createsubscriber.c | 34 ++++++-------
src/bin/pg_basebackup/t/040_pg_createsubscriber.pl | 6 +--
3 files changed, 49 insertions(+), 50 deletions(-)