Version 5.0.0 for AR 3.2

[cfis]

Hi everyone,

I've just pushed up a new release to rubygems.org that works with
ActiveRecord 3.2. Change log:

* Fix tests so they pass on MySql (Charlie Savage)
* Fix calculations to work with duplicate column names (cleesmith)
* Switch rake tasks for Postgresql and MySql to use ActiveRecord API
for
creating and dropping databases (Charlie Savage)
* Follow AR 3.2 lead and introduce self.primary_keys and deprecate
set_primary_keys (Charlie Savage)
* Switch from set_primary_key to self.primary_key= to avoid Rails
deprecation (Charlie Savage)
* Fix issue when using multiple database connections (David Doan)
* Fix homepage in gemspec and remove email address (Charlie Savage)
* Add support for string keys to exists? (Jan Vlnas)
* Fix typo (Jason Karns)

Thanks,

Charlie