[pgpool-committers: 8753] 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=aa12c1bf5db7e897a6a4a6d76168b4b86f61c8b4

Modified Files
--------------
doc.ja/src/sgml/release-3.7.sgml | 128 ++++++++++++++++++
doc.ja/src/sgml/release-4.0.sgml | 147 ++++++++++++++++++++
doc.ja/src/sgml/release-4.1.sgml | 237 ++++++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.2.sgml | 282 +++++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-3.7.sgml    | 124 +++++++++++++++++
doc/src/sgml/release-4.0.sgml    | 143 ++++++++++++++++++++
doc/src/sgml/release-4.1.sgml    | 210 +++++++++++++++++++++++++++++
doc/src/sgml/release-4.2.sgml    | 264 ++++++++++++++++++++++++++++++++++++
8 files changed, 1535 insertions(+)