Creating a new gem version

1. Generate a github token for your github username.
2. Run export CHANGELOG_GITHUB_TOKEN="«your-40-digit-github-token»"
3. Update the VERSION in lib/acts_as_list/version.rb with the new version of the gem. Commit and push the change.
4. Run rake release.
5. Run rake changelog.
6. Check the changelog file, then commit it with the message 'Updated changelog' and push.