Fix a few benign typos

Following on #4.

Those are very benign typos, but worth fixing anyway.

Also, I took a look at the roadmap and have a few suggestions:

> A list of fixes for third-party scripts with InstantClick, much like Turbolinks Compatibility, is badly needed.

IMHO it could be very simple yet useful: a simple GitHub repo with examples for each 3rd party script. You just have to setup the repo and do a few major examples, then put some contributing guidelines and let users fork the repo and add their own integrations.

> An Expo/showcase of sites using InstantClick would be great

Same as above, can be as simple as another forkable GitHub repo (+ gh-pages branch) with a json file that people could amend (à la https://github.com/npm/npm-expansions).

> A forum for getting help with InstantClick

Do you know about [Gitter](https://gitter.im/)? it seems to be one of the easiest way to setup a "help zone" for an OSS project hosted on GitHub.