pgsql: Tsvector editing functions

Tsvector editing functions

Adds several tsvector editting function: convert tsvector to/from text array,
set weight for given lexemes, delete lexeme(s), unnest, filter lexemes
with given weights

Author: Stas Kelvich with some editorization by me
Reviewers: Tomas Vondram, Teodor Sigaev

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/6943a946c7e5eb72d53c0ce71f08a81a133503bd

Modified Files
--------------
doc/src/sgml/func.sgml                |  91 +++++-
doc/src/sgml/textsearch.sgml          |   4 +
src/backend/utils/adt/tsvector_op.c   | 563 ++++++++++++++++++++++++++++++++++
src/include/catalog/pg_proc.h         |  18 +-
src/include/tsearch/ts_type.h         |   7 +
src/test/regress/expected/tstypes.out | 221 ++++++++++++-
src/test/regress/sql/tstypes.sql      |  47 ++-
7 files changed, 933 insertions(+), 18 deletions(-)