Install webshims, working with Rails 4 and Turbolinks
Shim files. See webshims.js.coffee for why we have to do this.
Add jquery-turbolinks to allow use of standard jQuery events instead of Turbolinks' page:load, etc
Remove copy of webshims from public. Remove gem in prep for vendored submodule.
Use vendored version of webshims since webshims-rails gem doesn't play nicely with Rails 4.