pgsql: New features for tsearch2: 1 Comparison operation for tsquery 2

Log Message:
-----------
New features for tsearch2:
1 Comparison operation for tsquery
2 Btree index on tsquery
3 numnode(tsquery) - returns 'length' of tsquery
4 tsquery @ tsquery, tsquery ~ tsquery - contains, contained for tsquery.
Note: They don't gurantee exact result, only MAY BE, so it
useful only for speed up rewrite functions
5 GiST index support for @,~
6 rewrite():
select rewrite(orig, what, to);
select rewrite(ARRAY[orig, what, to]) from tsquery_table;
select rewrite(orig, 'select what, to from tsquery_table;');
7 significantly improve cover algorithm

Modified Files:
--------------
pgsql/contrib/tsearch2:
Makefile (r1.10 -> r1.11)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/Makefile.diff?r1=1.10&r2=1.11)
query.c (r1.19 -> r1.20)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/query.c.diff?r1=1.19&r2=1.20)
query.h (r1.4 -> r1.5)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/query.h.diff?r1=1.4&r2=1.5)
rank.c (r1.12 -> r1.13)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/rank.c.diff?r1=1.12&r2=1.13)
tsearch.sql.in (r1.11 -> r1.12)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/tsearch.sql.in.diff?r1=1.11&r2=1.12)
pgsql/contrib/tsearch2/expected:
tsearch2.out (r1.13 -> r1.14)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/expected/tsearch2.out.diff?r1=1.13&r2=1.14)
pgsql/contrib/tsearch2/sql:
tsearch2.sql (r1.8 -> r1.9)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/sql/tsearch2.sql.diff?r1=1.8&r2=1.9)

Added Files:
-----------
pgsql/contrib/tsearch2:
query_cleanup.c (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/query_cleanup.c?rev=1.1&content-type=text/x-cvsweb-markup)
query_cleanup.h (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/query_cleanup.h?rev=1.1&content-type=text/x-cvsweb-markup)
query_gist.c (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/query_gist.c?rev=1.1&content-type=text/x-cvsweb-markup)
query_rewrite.c (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/query_rewrite.c?rev=1.1&content-type=text/x-cvsweb-markup)
query_support.c (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/query_support.c?rev=1.1&content-type=text/x-cvsweb-markup)
query_util.c (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/query_util.c?rev=1.1&content-type=text/x-cvsweb-markup)
query_util.h (r1.1)
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/query_util.h?rev=1.1&content-type=text/x-cvsweb-markup)

Removed Files:
-------------
pgsql/contrib/tsearch2:
rewrite.c
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/rewrite.c)
rewrite.h
(http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/rewrite.h)