[pgpool-committers: 8414] pgpool: Add relase notes.

[Masaya Kawamoto]

Add relase notes.

Branch
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V4_0_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=c4f295bbc6aa070e72c317570ecf8aece4fc3e8e

Modified Files
--------------
doc.ja/src/sgml/release-3.7.sgml  | 199 +++++++++++++++++++++++++++++++++
doc.ja/src/sgml/release-4.0.sgml  | 222 ++++++++++++++++++++++++++++++++++++
doc.ja/src/sgml/restrictions.sgml |  19 +---
doc.ja/src/sgml/version.sgml      |   2 +-
doc/src/sgml/release-3.7.sgml     | 204 +++++++++++++++++++++++++++++++++
doc/src/sgml/release-4.0.sgml     | 229 ++++++++++++++++++++++++++++++++++++++
doc/src/sgml/restrictions.sgml    |  15 +--
doc/src/sgml/version.sgml         |   2 +-
8 files changed, 863 insertions(+), 29 deletions(-)