[pgpool-committers: 8613] pgpool: Doc: add release notes.

[Bo Peng]

Doc: add release notes.

Branch
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V3_7_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=a1076bc4f8487647601b69188b7ac8acf0f3ca9e

Modified Files
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doc.ja/src/sgml/release-3.7.sgml | 142 ++++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-3.7.sgml    | 143 +++++++++++++++++++++++++++++++++++++++
2 files changed, 285 insertions(+)