pgsql: Add some regression test cases for denormalized float8 input.

Add some regression test cases for denormalized float8 input.

This was submitted with the previous patch, but I'm committing it
separately to ease backing it out if these results prove too unportable.

Marti Raudsepp, after a proposal by Jeroen Vermeulen

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/500cf66d5522b39ddfdc26b309f8b5b0e385f42e

Modified Files
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.../expected/float8-exp-three-digits-win32.out | 19 +++++++++++++++++++
src/test/regress/expected/float8-small-is-zero.out | 19 +++++++++++++++++++
.../regress/expected/float8-small-is-zero_1.out | 19 +++++++++++++++++++
src/test/regress/expected/float8.out | 19 +++++++++++++++++++
src/test/regress/sql/float8.sql | 5 +++++
5 files changed, 81 insertions(+), 0 deletions(-)