Rewrite without using any Berkshelf code

Should just shell out to whatever berks you have installed.

@samdunne still interested? Maybe we can pair on this next week.
@reset tl;dr:

```ruby
require 'singleton`
class Foo
  include Singleton

  def initialize(cannot_have_any_args)
    # setup
    # this is only ever called once
  end

  def method_x
    # accessible via Foo.instance.method_x
  end
end
```

You'll often see this:

```ruby
require 'singleton'

class Foo
  class << self
    def method_missing(m, *args, &block)
      instance.send(m, *args, &block)
    end
  end
end
```

Which lets you do `Foo.method_x`.