Fix react warnings

[Bas van Dijk]

I'm seeing the following warnings in the console:

lib.js:18723 Warning: Something is calling a React component directly. Use a factory or JSX instead. See: http://fb.me/react-legacyfactory
lib.js:18723 Warning: React.renderComponent will be deprecated in a future version. Use React.render instead.

Note that I'm using react 0.12.2.

I'll look at this myself when I have some time but that's probably in a few weeks.

[Alex Sayers]

Fixed by c85a29b.