Charts

Improved display of injury data by using Highcharts.

I couldn't pull in the dependencies using bower, so I referred to their server files instead.

I've intentionally left out the "uninjured" data but it can be re-inserted if you feel that's important.

Otherwise I think this is wickedly cool. :-)

![image](https://f.cloud.github.com/assets/4085127/1951884/373a438c-8194-11e3-9d78-8f777fb64096.png)