WIP - Websites homepage perf

Spike on improving the performance of the index page for a particular location website. This is a subsequent topic branch off https://github.com/G5/g5-content-management-system/pull/456

https://www.pivotaltracker.com/story/show/79415538
ActiveRecord would be faster, but make sure you call first...

```Ruby
Website.where(slug: params[:id]).first
```