pgsql: Implement array version of jsonb_delete and operator

Implement array version of jsonb_delete and operator

This makes it possible to delete multiple keys from a jsonb value by
passing in an array of text values, which makes the operaiton much
faster than individually deleting the keys (which would require copying
the jsonb structure over and over again.

Reviewed by Dmitry Dolgov and Michael Paquier

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/d00ca333c338b40911e89939c3cc771025978595

Modified Files
--------------
doc/src/sgml/func.sgml | 8 ++++
src/backend/utils/adt/jsonfuncs.c | 86 +++++++++++++++++++++++++++++++++++++
src/include/catalog/pg_operator.h | 2 +
src/include/catalog/pg_proc.h | 3 +-
src/test/regress/expected/jsonb.out | 18 ++++++++
src/test/regress/sql/jsonb.sql | 4 ++
6 files changed, 120 insertions(+), 1 deletion(-)