pgsql: Improve word parser.

Log Message:
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Improve word parser.
 - improve file and path recognition
 - fix misspeling
 - improve tag recognition

Modified Files:
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    pgsql/contrib/tsearch2/wordparser:
        parser.c (r1.4 -> r1.5)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/wordparser/parser.c.diff?r1=1.4&r2=1.5)
        parser.h (r1.6 -> r1.7)
        (http://developer.postgresql.org/cvsweb.cgi/pgsql/contrib/tsearch2/wordparser/parser.h.diff?r1=1.6&r2=1.7)