CDATA sections are ignored

This pull request contains a test of an html example with a CDATA section where the CDATA values are ignored. E.g. : 

```
<html><body><div><![CDATA[test]]></div></body></html>
```
Should have the same dom as

```
<html><body><div>test</div></body></html>
```
But it is 

```
<html><body><div></div></body></html>
```

This issue is maybe related to the parser not jsdom.