Fix for issue #8

I found that the current way the scientific notation is being chunked, I would get this result:

```javascript
1.5e10  <  1.8e-2  <  1.52e5
```

So, it would be better to just chunk the entire notation for parsing. I found this really nice [regex for detecting scientific notation](http://stackoverflow.com/a/658662/145346) on StackOverflow, and ended up with this regex:

```javascript
re = /(^([+\-]?(?:0|[1-9]\d*)(?:\.\d*)?(?:[eE][+\-]?\d+)?)?$|^0x[0-9a-f]+$|\d+)/gi
```

I've also updated the scientific notation and added a number-first alphanumeric unit test.

Sorry, I got carried away cleaning up the repository!