[pgpool-committers: 9532] pgpool: Doc: add release notes.

[Chen Ningwei]

Doc: add release notes.

Branch
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V4_1_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=e658ed8ac6d97f7bea9c27e44819807017940453

Modified Files
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doc.ja/src/sgml/release-4.0.sgml | 110 ++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.1.sgml | 155 ++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.0.sgml    | 117 +++++++++++++++++++++++++++
doc/src/sgml/release-4.1.sgml    | 166 +++++++++++++++++++++++++++++++++++++++
4 files changed, 548 insertions(+)