[pgpool-committers: 9736] 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=5d0c320d71a297ec0fd24ff4056f7c14d6ce87b1

Modified Files
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doc.ja/src/sgml/release-4.1.sgml |  98 +++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.1.sgml    | 102 +++++++++++++++++++++++++++++++++++++++
2 files changed, 200 insertions(+)