TOC parser broken

It's not clear that the _toc.xml files are useful (the few that I examined were pretty incomplete), but the current parsing code doesn't match the schema in the XML files at all. The TOC parsing code expects a simple lists of elements at the top level of _toc.xml which contain `` and `<pageno>` elements, but the actual structure is:

``` xml
<ocr_analysis>
<version>1</version>
<toc>
<entry>
<level>1</level>
<refpage>
<page>
<name>7</name>
<leaf>17</leaf>
<index>16</index>
</page>
</refpage>
<title>
<word>
<text>\9I</text>
<box>209 401 347 327</box>
</word>
<word>
<text>?</text>
<box>400 401 447 331</box>
</word>
```