pgstatsinfo - pg_statsinfo: Add missingl include file .

Log Message:
-----------
Add missingl include file <sys/stat.h>.

Use PGXS automatically even if USE_PGXS is not specified
unless the source tree is built under $PGSRC/contrib.

Modified Files:
--------------
    pg_statsinfo:
        Makefile (r1.1 -> r1.2)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgstatsinfo/pg_statsinfo/Makefile?r1=1.1&r2=1.2)
    pg_statsinfo/bin:
        Makefile (r1.5 -> r1.6)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgstatsinfo/pg_statsinfo/bin/Makefile?r1=1.5&r2=1.6)
        logger.c (r1.23 -> r1.24)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgstatsinfo/pg_statsinfo/bin/logger.c?r1=1.23&r2=1.24)
    pg_statsinfo/lib:
        Makefile (r1.4 -> r1.5)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgstatsinfo/pg_statsinfo/lib/Makefile?r1=1.4&r2=1.5)
        libstatsinfo.c (r1.22 -> r1.23)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgstatsinfo/pg_statsinfo/lib/libstatsinfo.c?r1=1.22&r2=1.23)