[pgpool-committers: 8415] pgpool: Add release notes.

[Masaya Kawamoto]

Add release notes.

Branch
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V3_7_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=3c45f9f602f4344fb074baceeaebed253ac7c2f6

Modified Files
--------------
doc.ja/src/sgml/release-3.7.sgml  | 199 +++++++++++++++++++++++++++++++++++++
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/restrictions.sgml    |  15 +--
doc/src/sgml/version.sgml         |   2 +-
6 files changed, 412 insertions(+), 29 deletions(-)