Rails, Mongoid & Unicorn config for Heroku
You dont actually need to do this, so for people coming to view this question see:
http://mongoid.org/en/mongoid/docs/rails.html
"Unicorn and Passenger
When using Unicorn or Passenger, each time a child process is forked when using app preloading or smart spawning, Mongoid will automatically reconnect to the master database. If you are doing this in your application manually you may remove your code."
Though it would still be interesting to know what would be the equivalent Mongoid code.