[pgpool-committers: 9368] 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=e8ef5178661d935844fc20fadac7b26f513141d4

Modified Files
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doc.ja/src/sgml/release-4.0.sgml | 338 +++++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.1.sgml | 338 +++++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.2.sgml | 393 ++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.0.sgml    | 362 +++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.1.sgml    | 362 +++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.2.sgml    | 417 +++++++++++++++++++++++++++++++++++++++
6 files changed, 2210 insertions(+)