win32: include psycopg2 (postgresql) support

[matysek]

Since we include mysql support in the windows build, we could also include support for postgresql database (psycopg2 module).

To include it, it should be enough to install pyscopg2 bindings and use latest svn version of pyinstaller to create windows builds.

I tested simple example with including psycopg2 with sqlalchemy and it seems working.
Winxp, python 2.7, sqlalchemy 0.7.1, psycopg2 2.4.2 from http://www.stickpeople.com/projects/python/win-psycopg/

Tested code example:

import sqlalchemy

# import mysql and postgreql bindings
__import__('MySQLdb')
__import__('psycopg2')

[Tomas Groth (tomasgroth)]

This should be include since 2.2 (maybe even 2.0?)