Fix the case where random gems think fucking with at_exit is an OK thing todo.

spec_helper.rb

if defined?(RUBY_ENGINE) && RUBY_ENGINE == "ruby" && RUBY_VERSION >= "1.9"
  module Kernel
    alias :__at_exit :at_exit
    def at_exit(&block)
      __at_exit do
        exit_status = $!.status if $!.is_a?(SystemExit)
        block.call
        exit exit_status if exit_status
      end
    end
  end
end

btw: http://www.davekonopka.com/2013/rspec-exit-code.html