[pgpool-committers: 8151] pgpool: Add release notes for Pgpool-II 4.0.16

[Masaya Kawamoto]

Add release notes for Pgpool-II 4.0.16

Branch
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V4_0_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=3ac3fa2ef7d967535af0b610bff40cf0301fec6b

Modified Files
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doc.ja/src/sgml/release-3.6.sgml | 166 ++++++++++++++++++++++++++++++++
doc.ja/src/sgml/release-3.7.sgml | 177 ++++++++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.0.sgml | 193 +++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-3.6.sgml    | 175 ++++++++++++++++++++++++++++++++++
doc/src/sgml/release-3.7.sgml    | 185 +++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.0.sgml    | 201 +++++++++++++++++++++++++++++++++++++++
6 files changed, 1097 insertions(+)