[pgpool-committers: 9868] pgpool: Doc: add release notes.

[Bo Peng]

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=96e0da5af31cedf0c4ad2954ea8b8c3c2ea638ae

Modified Files
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doc.ja/src/sgml/release-4.1.sgml | 180 ++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.1.sgml    | 192 +++++++++++++++++++++++++++++++++++++++
2 files changed, 372 insertions(+)