[pgpool-committers: 1789] pgpool: Fix release notes' style and add missing notes

[Yugo Nagata]

Fix release notes' style and add missing notes

Branch
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V3_1_STABLE

Details
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http://git.postgresql.org/gitweb?p=pgpool2.git;a=commitdiff;h=395af02f72ff14b78fb065cce20cd36d2e6d456b

Modified Files
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NEWS               | 3036 ++++++++++++++++++++++++++++++++++++----------------
doc/pgpool-ja.html | 1543 ++++++++++++++++----------
2 files changed, 3100 insertions(+), 1479 deletions(-)