pgsql: Detect invalid permutations in isolationtester

Detect invalid permutations in isolationtester

isolationtester is now able to continue running other permutations when
it detects that one of them is invalid, which is useful during initial
development of spec files.

Author: Alexander Shulgin

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/7064fd06489e069d38a9d67c5322265cb8f7ceec

Modified Files
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src/test/isolation/isolationtester.c |   48 +++++++++++++++++++++++++++++++++-
1 files changed, 47 insertions(+), 1 deletions(-)