Use d3 selected elements in init
Merge branch 'master' of github.com:trademapper/trademapper-js

* 'master' of github.com:trademapper/trademapper-js:
  html layout of interface with filter panel and colour changes
Merge branch 'master' of github.com:trademapper/trademapper-js

* 'master' of github.com:trademapper/trademapper-js:
  minor edit - add closing tag to <textarea>
Move divs around slightly
Load form bits from html fragments

Using the requirejs text plugin

This allows us to have a much simpler index.html, so if we want to have
a custom branded one later, it should be easier.