Drop fastclick, refs item:557

According to [fastclick#when-it-isnt-needed][1], if `width=device-width` or
`user-scalable=no` is set in the viewport meta tag, Chrome for Android will not
have a 300ms tap delay (FastClick checks for these tags and doesn't attach if
present).

We have both of those attributes set and are only targeting Android.

[1]: https://github.com/ftlabs/fastclick#when-it-isnt-needed