pgsql: Fix concat() and format() to handle VARIADIC-labeled arguments c

Fix concat() and format() to handle VARIADIC-labeled arguments correctly.

Previously, the VARIADIC labeling was effectively ignored, but now these
functions act as though the array elements had all been given as separate
arguments.

Pavel Stehule

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/760f3c043ad4ee622b596d005ec31bb5e0322c4a

Modified Files
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doc/src/sgml/func.sgml             |   24 ++++-
doc/src/sgml/xfunc.sgml            |   11 ++-
src/backend/utils/adt/varlena.c    |  198 +++++++++++++++++++++++++++++++-----
src/test/regress/expected/text.out |   89 ++++++++++++++++-
src/test/regress/sql/text.sql      |   23 ++++-
5 files changed, 310 insertions(+), 35 deletions(-)