pgsql: Improve psql's \d output for TOAST tables.

Improve psql's \d output for TOAST tables.

Add the name of the owning table to the footers for a TOAST table.
Also, show all the same footers as for a regular table (in practice,
this adds the index and perhaps the tablespace and access method).

Justin Pryzby, reviewed by Fabien Coelho

Discussion: https://postgr.es/m/20190422154902.GH14223@telsasoft.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/eb5472da9f83c2e432ac27a053929947e354d20c

Modified Files
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src/bin/psql/describe.c            | 37 ++++++++++++++++++++++++++++++++++---
src/test/regress/expected/psql.out | 12 ++++++++++++
src/test/regress/sql/psql.sql      |  3 +++
3 files changed, 49 insertions(+), 3 deletions(-)