pgsql: Add expected isolationtester output when prepared xacts are disa

Add expected isolationtester output when prepared xacts are disabled

This was deemed unnecessary initially but in later discussion it was
agreed otherwise.

Original file from Kevin Grittner, allegedly from Dan Ports.
I had to clean up whitespace a bit per changes from Heikki.

Branch
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REL9_1_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/0b298bd7a1782fca621068a5e17681be207f5635

Modified Files
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.../isolation/expected/prepared-transactions_1.out |41529 ++++++++++++++++++++
src/test/isolation/isolation_schedule              |    4 -
2 files changed, 41529 insertions(+), 4 deletions(-)