[pgpool-committers: 8153] pgpool: Add release notes for Pgpool-II 3.6.28

[Masaya Kawamoto]

Add release notes for Pgpool-II 3.6.28

Branch
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V3_6_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=aad5dc3540e953b7bbfc4933913adef3d31e8e27

Modified Files
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doc.ja/src/sgml/release-3.6.sgml | 166 +++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-3.6.sgml    | 175 +++++++++++++++++++++++++++++++++++++++
2 files changed, 341 insertions(+)