pgsql: Add array_remove() and array_replace() functions.

Add array_remove() and array_replace() functions.

These functions support removing or replacing array element value(s)
matching a given search value.  Although intended mainly to support a
future array-foreign-key feature, they seem useful in their own right.

Marco Nenciarini and Gabriele Bartolini, reviewed by Alex Hunsaker

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/84a42560c82aeb9f3690d93a0d03cf544f53b89b

Modified Files
--------------
doc/src/sgml/func.sgml               |   29 ++++
src/backend/utils/adt/arrayfuncs.c   |  306 ++++++++++++++++++++++++++++++++++
src/include/catalog/catversion.h     |    2 +-
src/include/catalog/pg_proc.h        |    4 +
src/include/utils/array.h            |    2 +
src/test/regress/expected/arrays.out |   62 +++++++
src/test/regress/sql/arrays.sql      |   11 ++
7 files changed, 415 insertions(+), 1 deletions(-)