[pgpool-committers: 10039] 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=3276366dbb74c98d23606fd376784d79641a4880

Modified Files
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doc.ja/src/sgml/release-4.1.sgml | 168 +++++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.2.sgml | 196 ++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.1.sgml    | 181 +++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.2.sgml    | 210 +++++++++++++++++++++++++++++++++++++++
4 files changed, 755 insertions(+)