Ada cooks

Please take a look at the form/method for adding measurements to a recipe. I had trouble with this because it only worked sometimes. When it wasn't working, the "Add ingredients" submit button did nothing when clicked. This made it difficult to troubleshoot, since nothing showed up on the rails server page or the network page when I inspected the element, nor was there any kind of error. Thank you! 
Instead of submitting the `session[:user_id]` through a hidden field, you could just use `session` in the controller that receives the request.