Add major features list and introductory text for 9.1 release notes.
Backpatch to 9.1, obviously.
Branch
------
master
Details
-------
http://git.postgresql.org/pg/commitdiff/eb72adc82e933f135369d846c2151c7694ffaa36
Modified Files
--------------
doc/src/sgml/release-9.1.sgml | 90 ++++++++++++++++++++++++++++++++++++++--
1 files changed, 85 insertions(+), 5 deletions(-)