Create named destinations for all boxes having an ID.

You can now add <a name="my-destination" /> to the input HTML and then jump directly to this location by passing the destination name as argument when opening the PDF.

This also adds named destinations for elements with id attributes.

Example HTML:
```
<html xmlns="http://www.w3.org/1999/xhtml" lang="en">

<head>
<title>Named Destinations Test</title>
</head>

<body>
    <p id="first-destination">
        This is the first page.
    </p>
    <p style="page-break-before: always;">
        <a name="second-destination"/>
        This is the second page.
    </p>
</body>

</html>
```

Open the resulting PDF with a command like this:
```
"C:\Program Files\Adobe\Reader 10.0\Reader\AcroRd32.exe" /A nameddest=second-destination test_default_ua.pdf
```

The reader should jump to the paragraph on the second page as soon as the PDF is opened.