pgsql: Add some platform-independent tests for the collation feature.

Add some platform-independent tests for the collation feature.

There's a lot we can't test very well without platform dependencies,
but the C/POSIX collations should now work the same way everywhere.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/9b095fbea4d6e80e3288e08bd2af4f33aa66875e

Modified Files
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src/test/regress/expected/collate.out |  554 +++++++++++++++++++++++++++++++++
src/test/regress/parallel_schedule    |    6 +-
src/test/regress/serial_schedule      |    1 +
src/test/regress/sql/collate.sql      |  193 ++++++++++++
4 files changed, 753 insertions(+), 1 deletions(-)