Users can delete links on edit page

I use javascript (written in coffeescript) to delete a link via the edit page
Since I'm using nested forms (I have a form for `packages`, but I want to show the `package.links` from another table/model, and `packages.attachements` from another table/model) I have to explicitly allow `:_destroy` in the params.

I'm trying to let users delete a `link` item, through a form on `package`. I do that through a `hidden_field` passing in the value `:_destroy` in the `_link.html.erb` partial. This is just letting it get through params