pgsql: Simplify options in pg_dump and pg_restore.

Simplify options in pg_dump and pg_restore.

Remove redundant options --with-data and --with-schema, and rename
--with-statistics to just --statistics.

Reviewed-by: Nathan Bossart <nathandbossart(at)gmail(dot)com>
Reviewed-by: Fujii Masao <masao(dot)fujii(at)gmail(dot)com>
Discussion: https://postgr.es/m/[email protected]
Backpatch-through: 18

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/6a46089e458f2d700dd3b8c3f6fc782de933529a

Modified Files
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doc/src/sgml/ref/pg_dump.sgml | 38 ++++--------
doc/src/sgml/ref/pg_dumpall.sgml | 38 ++++--------
doc/src/sgml/ref/pg_restore.sgml | 40 ++++---------
src/bin/pg_dump/pg_dump.c | 43 ++++----------
src/bin/pg_dump/pg_dumpall.c | 16 +----
src/bin/pg_dump/pg_restore.c | 35 ++++-------
src/bin/pg_dump/t/002_pg_dump.pl | 124 +++++++++++++++++++--------------------
src/bin/pg_upgrade/dump.c | 2 +-
8 files changed, 118 insertions(+), 218 deletions(-)