This gem will rebuild your .gems file for Heroku to match the current
contents of your Isolate file each time it is loaded.

Note: Due to Aspen having an outdated version of RubyGems, Isolate
      will only install cleanly on the Bamboo stacks. In theory, it
      should be possible to only load Isolate if you're not running
      under heroku, but it's probably easier just to migrate up.

Recommended installation is:

  # Isolate
  gem "isolate-heroku"

  # early in your app loading cycle
  require "isolate/now"
  require "isolate/heroku"

Note that this plugin will only make changes to your local .gems file,
you still need to commit it yourself.

See http://www.jbarnette.com/2010/06/26/isolate-on-heroku.html for
original motivation.