[pgpool-committers: 9099] 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=d72a17db85cd2225b7c387d5178b9f885f37c37c

Modified Files
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doc.ja/src/sgml/release-4.0.sgml | 165 +++++++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.1.sgml | 165 +++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.0.sgml    | 194 +++++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.1.sgml    | 194 +++++++++++++++++++++++++++++++++++++++
4 files changed, 718 insertions(+)