Update README.md
Merge pull request #261 from theo-bittencourt/patch-1

Update README.md - fix typo
Use hostname instead of host

``link.host`` may also return the port number contrary to ``location.host``
Merge pull request #263 from EmmanuelVella/patch-1

Use hostname instead of host
Use window location when form action is empty
Merge branch 'master' of https://github.com/defunkt/jquery-pjax
Ensure _pjax parameter is correctly added to 'data' depending on whether it's an object or array