[Pgpool-committers] pgpool - pgpool-II: Add restriction for parallel mode.

[User Kitagawa]

Log Message:
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Add restriction for parallel mode.
This is the same description as the manual of V2_2_STABLE.

- The Natural Join is not supported.
- The USING CLAUSE is converted to ON CLAUSE by query rewrite process.

Modified Files:
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    pgpool-II/doc:
        pgpool-en.html (r1.41 -> r1.42)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgpool/pgpool-II/doc/pgpool-en.html?r1=1.41&r2=1.42)
        pgpool-ja.html (r1.70 -> r1.71)
        (http://cvs.pgfoundry.org/cgi-bin/cvsweb.cgi/pgpool/pgpool-II/doc/pgpool-ja.html?r1=1.70&r2=1.71)