Upgrade React 0.10.0 -> 0.12.1

- also upgrade react-tools which provides the `jsx` binary.
- `renderComponent` deprecated, rename to `render`

https://www.pivotaltracker.com/story/show/84455892 [Delivers #84455892]
Merge pull request #58 from sealevelresearch/upgrade-react

Upgrade React 0.10.0 -> 0.12.1