[pgpool-committers: 8970] pgpool: Doc: add release note.

[Bo Peng]

Doc: add release note.

Branch
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V3_7_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=6080edf8f0938e07007fb4428cb46329205f536e

Modified Files
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doc.ja/src/sgml/release-3.7.sgml | 117 +++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-3.7.sgml    | 123 +++++++++++++++++++++++++++++++++++++++
2 files changed, 240 insertions(+)