Document wrapper indexing does not account for content type

[AntonOellerer]

Due to changes in the workings of the document wrapper, accessing paragraphs or tables now does not account for the specific type anymore, but has to be specified in total offset from the start.

For example, a document which has one text paragraph followed by one table followed by one text paragraph would have to be navigated in the following way documentWrapper.getParagraph(0), documentWrapper.getTable(1), documentWrapper.getParagraph(2).
While this is of course more direct, it takes away from the power of the library in my opinion, since developers now have to keep this in their mind as they develop tests.

[AntonOellerer]

@alexpartsch opinions?