Improves and reorganizes how nlp pipelines are setup. Now users can
choose from many options, depending on their hardware and usage
scenario.
This is the base to use more languages without depending on what
stanford-nlp supports. Support then is involves to text extraction and
simple regex-ner processing.
- Use another external tool to convert pdf to pdf which also adds the
extracted text as another layer into the pdf
- Although not used, the external conversion routine will now check
for an existing text file that is named as the pdf file with extension
`.txt`. If present it is included in the conversion result and will be
used as the extracted text.
- text extraction for pdf files happens now on the converted file,
because it may already contain the text from the conversion step and
thus avoids running OCR twice.
- All errors during conversion are not fatal; processing continues
without a converted file.
