Spree::Core::Engine.routes.prepend do

  namespace :admin do

    resources :relation_types
    resources :products do
      get :related, :on => :member
      resources :relations do
      	collection do
        	post :update_positions
    	end
      end
    end
      
  end

end

Spree::Core::Engine.routes.draw do
  namespace :admin do
    resources :relation_types
    resources :products, only: [] do
      get :related, :on => :member
      resources :relations do
      	collection do
        	post :update_positions
    	end
      end
    end
  end
end

Use draw to avoid mutliple declarations
Use draw to avoid mutliple declarations

Otherwise the routes are declared three times.
In addition used the only option to avoid redraw of product resource
links. Probably also solves #58

Fixes #71
