textsearch-ja - textsearch_groonga: Support VACUUM and add a test for

Log Message:
-----------
Support VACUUM and add a test for parallel updates.
Fix a bug to initialize scan keys.

Modified Files:
--------------
textsearch_groonga:
Makefile (r1.2 -> r1.3)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_groonga/Makefile?r1=1.2&r2=1.3)
textsearch_groonga.c (r1.6 -> r1.7)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_groonga/textsearch_groonga.c?r1=1.6&r2=1.7)
textsearch_groonga.sql.in (r1.5 -> r1.6)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_groonga/textsearch_groonga.sql.in?r1=1.5&r2=1.6)
textsearch_groonga/expected:
textsearch_groonga.out (r1.7 -> r1.8)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_groonga/expected/textsearch_groonga.out?r1=1.7&r2=1.8)
update.out (r1.1 -> r1.2)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_groonga/expected/update.out?r1=1.1&r2=1.2)
textsearch_groonga/sql:
textsearch_groonga.sql (r1.6 -> r1.7)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_groonga/sql/textsearch_groonga.sql?r1=1.6&r2=1.7)
update.sql (r1.1 -> r1.2)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_groonga/sql/update.sql?r1=1.1&r2=1.2)

Added Files:
-----------
textsearch_groonga/data:
bench.sql (r1.1)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_groonga/data/bench.sql?rev=1.1&content-type=text/x-cvsweb-markup)
textsearch_groonga/expected:
bench.out (r1.1)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_groonga/expected/bench.out?rev=1.1&content-type=text/x-cvsweb-markup)
textsearch_groonga/sql:
bench.sql (r1.1)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_groonga/sql/bench.sql?rev=1.1&content-type=text/x-cvsweb-markup)