pgsql: Add dummy_index_am to src/test/modules/

Add dummy_index_am to src/test/modules/

This includes more tests dedicated to relation options, bringing the
coverage of this code close to 100%, and the module can be used for
other purposes, like a base template for an index AM implementation.

Author: Nikolay Sharplov, Michael Paquier
Reviewed-by: Álvaro Herrera, Dent John
Discussion: /messages/by-id/17071942.m9zZutALE6@x200m

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/640c19869f8c4b5c34d3982b5e1cd40e62abbb85

Modified Files
--------------
src/test/modules/Makefile | 1 +
src/test/modules/dummy_index_am/.gitignore | 3 +
src/test/modules/dummy_index_am/Makefile | 20 ++
src/test/modules/dummy_index_am/README | 11 +
.../modules/dummy_index_am/dummy_index_am--1.0.sql | 19 ++
src/test/modules/dummy_index_am/dummy_index_am.c | 312 +++++++++++++++++++++
.../modules/dummy_index_am/dummy_index_am.control | 5 +
.../modules/dummy_index_am/expected/reloptions.out | 115 ++++++++
src/test/modules/dummy_index_am/sql/reloptions.sql | 68 +++++
src/tools/pgindent/typedefs.list | 1 +
10 files changed, 555 insertions(+)