Merge the two app logrotate rules

The gunicorn logrotate rules was causing gunicorn to escape its parent,
which when the application logrotate rules restarted the upstart job
would leave the upstart job spinning.

Merging the two jobs will achieve the same goal as gunicorn will restart
its logging when the parent upstart job is restarted.
Merge pull request #232 from alphagov/merge-rotates

Merge the two app logrotate rules