[pgpool-committers: 8258] pgpool: Add release notes.

[Masaya Kawamoto]

Add release notes.

Branch
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V4_3_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=2f8cb3e29b03a7d6ebf487c0485a4ed40271d5a2

Modified Files
--------------
doc.ja/src/sgml/release-3.7.sgml | 33 +++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.0.sgml | 33 +++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.1.sgml | 45 ++++++++++++++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.2.sgml | 45 ++++++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-3.7.sgml    | 33 +++++++++++++++++++++++++++++
doc/src/sgml/release-4.0.sgml    | 33 +++++++++++++++++++++++++++++
doc/src/sgml/release-4.1.sgml    | 45 ++++++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.2.sgml    | 45 ++++++++++++++++++++++++++++++++++++++++
8 files changed, 312 insertions(+)