Thread: pgsql: Add some comments to test_ddl_deparse and a README

Add some comments to test_ddl_deparse and a README

Per comments from Heikki Linnakangas.

Backpatch to 9.5, where this module was introduced.

Branch
------
REL9_5_STABLE

Details
-------
http://git.postgresql.org/pg/commitdiff/f1f3434f210450af2e3dab08fbc05a9edd0b67a4

Modified Files
--------------
src/test/modules/test_ddl_deparse/README           |    8 ++++++
.../modules/test_ddl_deparse/test_ddl_deparse.c    |   26 ++++++++++++++++++++
2 files changed, 34 insertions(+)