pgsql: Update citext extension for parallel query.

Update citext extension for parallel query.

All citext functions are PARALLEL SAFE, and a couple of them can
benefit from having aggregate combine functions.

Andreas Karlsson

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/a89b4b1be0d3550a7860250ff74dc69730555a1f

Modified Files
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contrib/citext/Makefile             |   3 +-
contrib/citext/citext--1.1--1.2.sql |  54 ++++
contrib/citext/citext--1.1.sql      | 489 -----------------------------------
contrib/citext/citext--1.2.sql      | 493 ++++++++++++++++++++++++++++++++++++
contrib/citext/citext.control       |   2 +-
5 files changed, 550 insertions(+), 491 deletions(-)