pgsql: Factor out encoding specific tests for json

Factor out encoding specific tests for json

This lets us remove the large alternative results files for the main
json and jsonb tests, which makes modifying those tests simpler for
committers and patch submitters.

Backpatch to 9.4 for jsonb and 9.3 for json.

Branch
------
REL9_4_STABLE

Details
-------
http://git.postgresql.org/pg/commitdiff/56f9d916327b3e256d655db278b62b850c931d91

Modified Files
--------------
src/test/regress/expected/json.out | 113 +-
src/test/regress/expected/json_1.out | 1643 ----------------
src/test/regress/expected/json_encoding.out | 247 +++
src/test/regress/expected/json_encoding_1.out | 243 +++
src/test/regress/expected/jsonb.out | 131 +-
src/test/regress/expected/jsonb_1.out | 2531 -------------------------
src/test/regress/parallel_schedule | 2 +-
src/test/regress/serial_schedule | 1 +
src/test/regress/sql/json.sql | 28 +-
src/test/regress/sql/json_encoding.sql | 68 +
src/test/regress/sql/jsonb.sql | 31 +-
11 files changed, 564 insertions(+), 4474 deletions(-)