[pgpool-committers: 10252] pgpool: Doc: add release notes.

[Bo Peng]

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=74efc4728654d62fdf1e45dfd5ad01ff10245fb0

Modified Files
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doc.ja/src/sgml/release-4.1.sgml | 194 ++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.2.sgml | 248 +++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.1.sgml    | 212 ++++++++++++++++++++++++++++++
doc/src/sgml/release-4.2.sgml    | 273 +++++++++++++++++++++++++++++++++++++++
4 files changed, 927 insertions(+)