Thread: pgsql: Explain max_prepared_transactions requirement in isolation tests

Explain max_prepared_transactions requirement in isolation tests' README.

Now that we have a test that requires nondefault settings to pass, it seems
like we'd better mention that detail in the directions about how to run the
tests.

Also do some very minor copy-editing.

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/6a42b29102092d185f9b752f5a4edf4735e42f9b

Modified Files
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src/test/isolation/README |   28 +++++++++++++++++++++++-----
1 files changed, 23 insertions(+), 5 deletions(-)