[pgpool-committers: 9530] pgpool: Doc: add release notes.

[Chen Ningwei]

Doc: add release notes.

Branch
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V4_4_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=b2501838fa1a4da2d8c9eb800e4578a7fd1aa9fd

Modified Files
--------------
doc.ja/src/sgml/release-4.0.sgml | 110 ++++++++++++
doc.ja/src/sgml/release-4.1.sgml | 155 +++++++++++++++++
doc.ja/src/sgml/release-4.2.sgml | 216 ++++++++++++++++++++++++
doc.ja/src/sgml/release-4.3.sgml | 216 ++++++++++++++++++++++++
doc.ja/src/sgml/release-4.4.sgml | 329 ++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.0.sgml    | 117 +++++++++++++
doc/src/sgml/release-4.1.sgml    | 166 ++++++++++++++++++
doc/src/sgml/release-4.2.sgml    | 227 +++++++++++++++++++++++++
doc/src/sgml/release-4.3.sgml    | 227 +++++++++++++++++++++++++
doc/src/sgml/release-4.4.sgml    | 354 +++++++++++++++++++++++++++++++++++++++
10 files changed, 2117 insertions(+)