More structural ideas

Updated the sass and js file/folder structure to reflect a more component based approach.

In this build, there is no longer a separation of `sass` and `js` filetypes - instead, the app folder is organised based on _components_ within the website. At the root directory you can now see:

- Main files to be compiled through gulp - `application.js`, `application.scss` and `index.html`.
- The `_shamefile.scss` for sloppy styling when you need it.
- The main javascript components and their existing organisation of libs, pages and widgets.
- A `core` folder, currently housing the global styles, but could also be used for global application code (eg, a router if we add one?).
- The same old assets folder, used for any static assets which need to be copied into build, or referenced from css.

I think that this approach will serve us well, given that our sass setup (in a separate folder) would have likely began to reflect the js components anyway. Now when we're working on the style &/or behavioural code for a widget, or specific structural element within the app - there's a single place we can look at within our app structure for both.