Upgrade to Rails 3
Using AR 3 query API
This is a temporal fix
Remove Date.today from gemspec

Processing this gemfile gives an exception on bundler 1.3.5 and rubygems 1.8.25 due to the inexistance of Date.today. Other widely used gems do not use the date metadata.
Improve boot time using active support callbacks
Split callbacks to set the persistized value:

- before_create the record always changed
- before_update only when the record changed
Prepare new version