[pgpool-committers: 8972] pgpool: Doc: add release note.

[Bo Peng]

Doc: add release note.

Branch
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V4_1_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=0479935c512cb6b34a3e820aca63699b70383424

Modified Files
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doc.ja/src/sgml/release-3.7.sgml | 117 ++++++++++++++++++++
doc.ja/src/sgml/release-4.0.sgml | 212 ++++++++++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.1.sgml | 212 ++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-3.7.sgml    | 123 +++++++++++++++++++++
doc/src/sgml/release-4.0.sgml    | 224 +++++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.1.sgml    | 224 +++++++++++++++++++++++++++++++++++++++
6 files changed, 1112 insertions(+)