pgsql: Update postgresql.conf.sample to match pg_settings classificaito

Update postgresql.conf.sample to match pg_settings classificaitons.

A handful of settings, most notably shared_preload_libraries, were
just plain the wrong place compared to their assigned config_group
value in guc.c (and thus pg_settings). In other cases the names of
the sections in postgresql.conf.sample were mildly different from
the corresponding entries in config_group_names[]. Make it all
consistent.

Adrián Escoms, reviewed by me.

Discussion: http://postgr.es/m/CACksPC2veEmFRYqwYepWYO9U7aFhAx6sYq+WqjTyHw7uV=E=pw@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/79f2d637139f117a7be2e751328b504f1decd9b7

Modified Files
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src/backend/utils/misc/postgresql.conf.sample | 32 +++++++++++++++------------
1 file changed, 18 insertions(+), 14 deletions(-)