fix &amp; issue end of string

In case of this html:

```html
<code>
en:
  activerecord:
    errors:
      models:
        user:
          attributes:
            password:
              invalid: "Must include uppercase &amp; number
</code>
```

parser rendered:

```
en:
  activerecord:
    errors:
      models:
        user:
          attributes:
            password:
              invalid: 'Must include uppercase &;; number'
```

this will fix that issue
Merge pull request #1 from equivalent/fix_amp

fix &amp; issue end of string