[pgpool-committers: 4656] pgpool: Add release notes 3.7.3 - 3.3.21.

[Bo Peng]

Add release notes 3.7.3 - 3.3.21.

Branch
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V3_6_STABLE

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=0a68446e2a7629cb1e03ed5e47caf216f3d0499e

Modified Files
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doc.ja/src/sgml/release-3.3.sgml |  33 +++++++++
doc.ja/src/sgml/release-3.4.sgml |  81 ++++++++++++++++++++++
doc.ja/src/sgml/release-3.5.sgml |  93 +++++++++++++++++++++++++
doc.ja/src/sgml/release-3.6.sgml | 142 +++++++++++++++++++++++++++++++++++++++
doc.ja/src/sgml/version.sgml     |   2 +-
doc/src/sgml/release-3.3.sgml    |  24 +++++++
doc/src/sgml/release-3.4.sgml    |  63 +++++++++++++++++
doc/src/sgml/release-3.5.sgml    |  69 +++++++++++++++++++
doc/src/sgml/release-3.6.sgml    | 109 ++++++++++++++++++++++++++++++
doc/src/sgml/version.sgml        |   2 +-
10 files changed, 616 insertions(+), 2 deletions(-)