[pgpool-committers: 4657] 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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master

Details
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https://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=c383981a24ff9307035e4bbc42cb20ffb811f8a0

Modified Files
--------------
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/release-3.7.sgml | 239 +++++++++++++++++++++++++++++++++++++++
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/release-3.7.sgml    | 200 ++++++++++++++++++++++++++++++++
10 files changed, 1053 insertions(+)