Js improvements

Fixes #281 and fixes #273

- Adds fastclick
- Move customer js to the bottom of the page
- Move comment hash JS helpers to Timber's `shop.js`
- Move login/recover password JS to Timber's `shop.js`

Demo shop for new updates - http://steve-dev.myshopify.com/

@stevebosworth @mpiotrowicz 
i'm not sure that these need to be saved onto the Timber namespace as it's a little unexpected that you'd potentially be defining `timber` in this little page-script, and I'm not sure what nesting under `global` gives you, especially since this is very page specific (eg something like the cart is global, available on every page).