pgsql: Rename tsvector delete() to ts_delete(), and filter() to ts_filt

Rename tsvector delete() to ts_delete(), and filter() to ts_filter().

The similarity of the original names to SQL keywords seems like a bad
idea. Rename them before we're stuck with 'em forever.

In passing, minor code and docs cleanup.

Discussion: <4875(dot)1462210058(at)sss(dot)pgh(dot)pa(dot)us>

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/0b9a23443283f9ffb17a39c25f74adefdb72cae1

Modified Files
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doc/src/sgml/func.sgml | 132 +++++++++++++++++-----------------
doc/src/sgml/textsearch.sgml | 3 +-
src/backend/utils/adt/tsvector_op.c | 17 ++---
src/include/catalog/catversion.h | 2 +-
src/include/catalog/pg_proc.h | 12 ++--
src/test/regress/expected/tstypes.out | 58 +++++++--------
src/test/regress/sql/tstypes.sql | 32 ++++-----
7 files changed, 128 insertions(+), 128 deletions(-)