OCR demo blobconverter

[Erol444]

Use blobconverter for the gen2-ocr experiment. 1st stage NN is the text detection model, which can be found on PINTOs model zoo. We would preferably upload xml/bin to artifactory and pass URL to the blobconverter, so IR model would get downloaded&compiled on the server. 2nd NN is text-recognition-0012 model, which can found on OMZ.