adding setMaxListeners(0) to EventEmitter instances in, prevents JS erro...

...r in console.  Your forked version of the the react-router is being used on [https://www.atlassian.com/git/](https://www.atlassian.com/git/), and you'll see the following console message:

```
(node) warning: possible EventEmitter memory leak detected. 11 listeners added. Use emitter.setMaxListeners() to increase limit. 
```
This is coming from the react-router, not the application code.  This pull request should fix it.