Browser Version

I quickly ran the code through `browserify` to make that working in the browser.

**Good Thing**

```bash
npm install
npm run build-browser
echo "<script src="joblint.js"></script><script>console.log(joblint(prompt('Copy/paste a spec here')))</script>" > demo.html && open demo.html
```
And look at the result in the console.
I had the same results as the Node execution.

**Bad Thing**

For some reason, the mocks make things complicated test. I haven't spent many time on the problem so it might be obvious but well.

```bash
npm run test-browser
```