Adds instructions to README for adding to a Rails app

[cannikin]

I've been including the full turbolinks repo until I found this gem that just includes the final compiled JS, which is probably all that most people need. There weren't any instructions for installing into Rails, so I added some!

[packagethief]

Hey @cannikin,

Quickly add Turbolinks to your Rails app without the overhead of coffeescript and building the compiled JS from source

I think there's some confusion, probably because of the Gem name. The turbolinks Gem actually resolves to turbolinks-rails – the Rails engine. turbolinks-rails in turn specifies turbolinks-source as a dependency.

So, you're cool to depend on gem "turbolinks" in your Gemfile. There's no CoffeeScript dependency, and no building from source. It's just the minified JavaScript plus the Rails integration (which you probably want). You shouldn't ever need to depend on turbolinks-source directly.

[cannikin]

Ahhhhhhh that explains things then. :) I assumed that the gem turbolinks was from the repo turbolinks with the actual source files and such. So I figured on the first request it was compling the coffeescript into the actual JS that's included by the asset pipeline which seemed like a lot of work if all you needed was the compiled JS to begin with! :)

[packagethief]

Yeah, sorry about that. I can see why it would be confusing. I intend to add a README here that at least explains its purpose.