Created a pretty reporter

This is a simplified reporter from #283 
Can we get a spinner in here for the ones that are not 100% complete? Once per render loop:

```js
var spinner = '\';
var tick = 0;
var STATES = [ '/', '-', '\' ];

function next() {
  tick = (tick + 1) % 3;
  spinner = STATES[tick];
}
```