pgsql: Add casts from jsonb

Add casts from jsonb

Add explicit cast from scalar jsonb to all numeric and bool types. It would be
better to have cast from scalar jsonb to text too but there is already a cast
from jsonb to text as just text representation of json. There is no way to have
two different casts for the same type's pair.

Bump catalog version

Author: Anastasia Lubennikova with editorization by Nikita Glukhov and me
Review by: Aleksander Alekseev, Nikita Glukhov, Darafei Praliaskouski
Discussion: https://www.postgresql.org/message-id/flat/0154d35a-24ae-f063-5273-9ffcdf1c7f2e@postgrespro.ru

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/c0cbe00fee6d0a5e0ec72c6d68a035e674edc4cc

Modified Files
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src/backend/utils/adt/jsonb.c       | 175 ++++++++++++++++++++++++++++++++++++
src/include/catalog/catversion.h    |   2 +-
src/include/catalog/pg_cast.h       |   9 ++
src/include/catalog/pg_proc.h       |  16 ++++
src/test/regress/expected/jsonb.out | 105 ++++++++++++++++++++++
src/test/regress/sql/jsonb.sql      |  22 +++++
6 files changed, 328 insertions(+), 1 deletion(-)