Selection of OCR engine is now possible on the commandline. Use -E
<engine>, where engine can be abbyy(default), abbyy-multiuser, ocrsdk,
or tesseract.
New commandline options for -O:
1) abbyy.config=<file> where file is gbv-antiqua.properties or
gbv-fraktur.properties
2) abbyy.user=<username>
3) abbyy.password=<password>
debugging
doku
Same options "user" and "password" for all ocr engines.
OCR Engine can be chosen at runtime.