pgsql: docs: update release notes for 8.4.18, 9.0.14, 9.1.10, 9.2.5, 9

docs:  update release notes for 8.4.18, 9.0.14, 9.1.10, 9.2.5, 9.3.1

Branch
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REL9_3_STABLE

Details
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http://git.postgresql.org/pg/commitdiff/2589a5a59b9023b66710227750dab15cec68310f

Modified Files
--------------
doc/src/sgml/release-8.4.sgml |  193 ++++++++++++++++++++
doc/src/sgml/release-9.0.sgml |  257 ++++++++++++++++++++++++++
doc/src/sgml/release-9.1.sgml |  321 +++++++++++++++++++++++++++++++++
doc/src/sgml/release-9.2.sgml |  397 +++++++++++++++++++++++++++++++++++++++++
doc/src/sgml/release-9.3.sgml |   86 +++++++++
5 files changed, 1254 insertions(+)