textsearch-ja - textsearch_senna: Fix a bug that initial_n_segments

Log Message:
-----------
Fix a bug that initial_n_segments reloption is not accepted in 8.4.

Modified Files:
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textsearch_senna:
textsearch_senna.c (r1.7 -> r1.8)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_senna/textsearch_senna.c?r1=1.7&r2=1.8)
textsearch_senna/doc:
textsearch_senna.html (r1.2 -> r1.3)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_senna/doc/textsearch_senna.html?r1=1.2&r2=1.3)
textsearch_senna/expected:
textsearch_senna.out (r1.4 -> r1.5)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_senna/expected/textsearch_senna.out?r1=1.4&r2=1.5)
textsearch_senna/sql:
textsearch_senna.sql (r1.4 -> r1.5)
(http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/textsearch-ja/textsearch_senna/sql/textsearch_senna.sql?r1=1.4&r2=1.5)