Added Twitter timeline

I've been messing with the Twitter feeds for a different project and noticed the site was missing ours, it's probably low on the list of priorities but seemed like a quick fix? Up to you guys if you want to include it!

In keeping with the minimal theme, removed the footer, it seemed to look better keeping the border, even though it can be removed. Any thoughts?

Documentation here:
https://dev.twitter.com/web/embedded-timelines