pgsql: Add isolation test for SERIALIZABLE READ ONLY DEFERRABLE.

Add isolation test for SERIALIZABLE READ ONLY DEFERRABLE.

This improves code coverage and lays a foundation for testing
similar issues in a distributed environment.

Author: Thomas Munro <thomas.munro@enterprisedb.com>
Reviewed-by: Michael Paquier <michael.paquier@gmail.com>

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4deb413813f619b3e859abf435b61efc09cafe09

Modified Files
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.../isolation/expected/read-only-anomaly-2.out     | 44 ++++++++++++++++++++++
.../isolation/expected/read-only-anomaly-3.out     | 26 +++++++++++++
src/test/isolation/expected/read-only-anomaly.out  | 25 ++++++++++++
src/test/isolation/isolation_schedule              |  3 ++
src/test/isolation/isolationtester.c               |  8 ++++
src/test/isolation/specs/read-only-anomaly-2.spec  | 42 +++++++++++++++++++++
src/test/isolation/specs/read-only-anomaly-3.spec  | 39 +++++++++++++++++++
src/test/isolation/specs/read-only-anomaly.spec    | 38 +++++++++++++++++++
8 files changed, 225 insertions(+)