pgsql: Add point <-> polygon distance operator.

Add point <-> polygon distance operator.

Alexander Korotkov, reviewed by Emre Hasegeli.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/4520ba67691fc13bb8be2cc47dd0bf8c7ab94205

Modified Files
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src/backend/utils/adt/geo_ops.c       |   76 ++++++++++++++++++++++++++-------
src/include/catalog/pg_operator.h     |    2 +
src/include/catalog/pg_proc.h         |    1 +
src/include/utils/geo_decls.h         |    1 +
src/test/regress/expected/polygon.out |   11 +++++
src/test/regress/sql/polygon.sql      |    7 +++
6 files changed, 82 insertions(+), 16 deletions(-)