Finish off the fixes for Rails 4

I saw [in the official rails-footnotes repo](https://github.com/josevalim/rails-footnotes/pull/90) that you started a pull request to get it to boot for Rails 4. 

Thanks for that! :clap: 

The pull request I'm making to you finishes it off -- queries now appear at the bottom, and all of the deprecation notices are fixed.

If you accept my PR, these commits will be added to your PR on the official repo, and perhaps they'll merge it since support for Rails 4 will be complete.

:beers: Cheers!