Pglife and back-branch commits

Alvaro asked me to add the display of post minor-release commits to
PgLife (http://pglife.momjian.us/).  I have added a link to that
information as a plus-sign after each minor release number, e.g. Stable:
9.2.4+, 9.1.9+, 9.0.13+, 8.4.17+.

Hopefully this will be helpful in us scheduling minor releases.

--  Bruce Momjian  <bruce@momjian.us>        http://momjian.us EnterpriseDB
http://enterprisedb.com
 + It's impossible for everything to be true. +