[development] PostgreSQL support for 4.8 install system

Hi everyone, I've added pgsql support in the install system. I've added a few bells and whistles too. Most notably we now have unsigned smallint, int and bigint added in! Those become smalluint, uint and biguint. Check out http://drupal.org/node/76681 for install.pgsql.inc and the patch needed for system.install. I'm in need of testers to ensure the install system operates properly. Cheers, -- Sammy Spets Synerger Pty Ltd http://www.synerger.com/