pgsql: Update contrib/hstore for new GIN extractQuery API.

Update contrib/hstore for new GIN extractQuery API.

In particular, make hstore @> '' succeed for all hstores, likewise
hstore ?& '{}'. Previously the results were inconsistent and could
depend on whether you were using a GiST index, GIN index, or seqscan.

Branch
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master

Details
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http://git.postgresql.org/gitweb?p=postgresql.git;a=commitdiff;h=ba398969cd1b32c550345bcf6b713deeb0a7d1de

Modified Files
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contrib/hstore/expected/hstore.out | 2 +-
contrib/hstore/hstore_gin.c | 112 +++++++++++++++++++++---------------
contrib/hstore/hstore_op.c | 14 +++--
3 files changed, 75 insertions(+), 53 deletions(-)