Обсуждение: pgsql: Improve user-facing JSON documentation.

Improve user-facing JSON documentation.

I started out with the intention of just fixing the info about the jsonb
operator classes, but soon found myself copy-editing most of the JSON
material.  Hopefully it's more readable now.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/0b92a77c17ebe8bec08e250e1a929b07efef1008

Modified Files
--------------
doc/src/sgml/func.sgml        |  216 ++++++++++++---------------
doc/src/sgml/gin.sgml         |    2 +-
doc/src/sgml/json.sgml        |  328 ++++++++++++++++++++---------------------
doc/src/sgml/release-9.3.sgml |    4 +-
4 files changed, 255 insertions(+), 295 deletions(-)