[pgpool-committers: 10454] pgpool: Doc: add release notes.

[Taiki Koshino]

Doc: add release notes.

Branch
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V4_2_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=f0b94e80d049089e73c5db13ceb0333e3e3a1358

Modified Files
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doc.ja/src/sgml/release-4.2.sgml | 140 +++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.2.sgml    | 153 +++++++++++++++++++++++++++++++++++++++
2 files changed, 293 insertions(+)