This patch adds jquery-ujs file (rails.js) from
https://github.com/rails/jquery-ujs which enables forms and
links to submit data with Ajax just by adding :remote => true parameter to
it which creates data-remote="true" html5 attribute.
I think this rails3 feature comes handy in various places and should
definitelly be part of the application.
sample tutorial here:
http://blog.bernatfarrero.com/jquery-and-rails-3-mini-tutorial/