Move slide creation into JavaScript

So that we can easily create the slides based on some config
that we request from an HTTP API somewhere.
Improve style of full screen link
Upgrade frontend toolkit to 3.0.1

This one's for you, @easternbloc.
Merge pull request #16 from alphagov/tidying-slide-creation

Tidy slide creation
Add Google Analytics pageview tracking
Add Google Analytics event tracking

Sends 'heartbeat' event every half an hour
Merge pull request #17 from alphagov/google-analytics

Google analytics
Tweak design of big screen view

To be closer to the designs that were made.
Merge pull request #18 from alphagov/design-tweaks

Tweak design of big screen view
Improve README with dev instructions
Merge pull request #19 from alphagov/readme

Improve README with dev instructions
Slide styling, responsive fonts, use mock data file
Slide styles, dept background colours
Increase slide display interval to 10s
Use API instead of mock data file. Iterate through modules with _.each
Hide cursor on slides
Merge pull request #20 from alphagov/styles

Styles for slides
Add Performance Platform client to package.json

The app fails to run the browserify task during deployment without
the client being present.
Merge pull request #21 from alphagov/add-pp-client

Add Performance Platform client to package.json
Run unit tests via Karma