pgsql: Transforms for jsonb to PL/Python

Transforms for jsonb to PL/Python

Add a new contrib module jsonb_plpython that provide a transform between
jsonb and PL/Python. jsonb values are converted to appropriate Python
types such as dicts and lists, and vice versa.

Author: Anthony Bykov <a(dot)bykov(at)postgrespro(dot)ru>
Reviewed-by: Aleksander Alekseev <a(dot)alekseev(at)postgrespro(dot)ru>
Reviewed-by: Nikita Glukhov <n(dot)gluhov(at)postgrespro(dot)ru>

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/3f44e3db72ad4097aae078c075a9b3cb3d6b761b

Modified Files
--------------
contrib/Makefile | 4 +-
contrib/jsonb_plpython/.gitignore | 6 +
contrib/jsonb_plpython/Makefile | 39 ++
contrib/jsonb_plpython/expected/jsonb_plpython.out | 347 ++++++++++++++++
contrib/jsonb_plpython/jsonb_plpython.c | 453 +++++++++++++++++++++
contrib/jsonb_plpython/jsonb_plpython2u--1.0.sql | 19 +
contrib/jsonb_plpython/jsonb_plpython2u.control | 6 +
contrib/jsonb_plpython/jsonb_plpython3u--1.0.sql | 19 +
contrib/jsonb_plpython/jsonb_plpython3u.control | 6 +
contrib/jsonb_plpython/jsonb_plpythonu--1.0.sql | 19 +
contrib/jsonb_plpython/jsonb_plpythonu.control | 6 +
contrib/jsonb_plpython/sql/jsonb_plpython.sql | 218 ++++++++++
doc/src/sgml/json.sgml | 15 +
13 files changed, 1155 insertions(+), 2 deletions(-)