[pgpool-committers: 4022] 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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master

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=81228a019cc8d8eef865ad475353602203ab899e

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/src/sgml/release-3.5.sgml    | 34 +++++++++++++++++++++
doc/src/sgml/release-3.6.sgml    | 61 +++++++++++++++++++++++++++++++++++++
4 files changed, 199 insertions(+)