[pgpool-committers: 4023] pgpool: Add 3.6.4, 3.5.8 release notes.

[pengbo]

Add 3.6.4, 3.5.8 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=eb33a470297fddf7aa11a91f1822849b5525d5a0

Modified Files
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doc.ja/src/sgml/release-3.5.sgml | 38 +++++++++++++++++++++++
doc.ja/src/sgml/release-3.6.sgml | 66 ++++++++++++++++++++++++++++++++++++++++
doc.ja/src/sgml/version.sgml     |  2 +-
doc/src/sgml/release-3.5.sgml    | 34 +++++++++++++++++++++
doc/src/sgml/release-3.6.sgml    | 61 +++++++++++++++++++++++++++++++++++++
doc/src/sgml/version.sgml        |  2 +-
6 files changed, 201 insertions(+), 2 deletions(-)