[pgpool-committers: 8756] 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=1f766eea0057680c829ea8df513190859c6acec4

Modified Files
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doc.ja/src/sgml/release-3.7.sgml | 128 +++++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-3.7.sgml    | 124 +++++++++++++++++++++++++++++++++++++
2 files changed, 252 insertions(+)