[pgpool-committers: 7930] pgpool: Add release notes.

[Masaya Kawamoto]

Add release notes.

Branch
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V3_6_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=6ccbf7c6490e3136c5cb7da4b839ba74d88bd6b3

Modified Files
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doc.ja/src/sgml/release-3.6.sgml | 161 ++++++++++++++++++++++++++++++++++++++
doc.ja/src/sgml/version.sgml     |   2 +-
doc/src/sgml/release-3.6.sgml    | 163 +++++++++++++++++++++++++++++++++++++++
doc/src/sgml/version.sgml        |   2 +-
4 files changed, 326 insertions(+), 2 deletions(-)