genericvector: Pass parameters by reference
genericvector: Pass parameters by reference

This fixes warnings like the following one from LGTM:

This parameter of type ParamsTrainingHypothesis is 112 bytes
- consider passing a pointer/reference instead.

Most parameters can also get the const attribute.

Signed-off-by: Stefan Weil <8d4c780fcfdc41841e5070f4c43da8958ba6aec0@weilnetz.de>

stweil/tesseract,jbarlow83/tesseract,UB-Mannheim/tesseract,amitdo/tesseract,tesseract-ocr/tesseract,amitdo/tesseract,stweil/tesseract,UB-Mannheim/tesseract,amitdo/tesseract,stweil/tesseract,stweil/tesseract,jbarlow83/tesseract,UB-Mannheim/tesseract,UB-Mannheim/tesseract,jbarlow83/tesseract,tesseract-ocr/tesseract,jbarlow83/tesseract,amitdo/tesseract,tesseract-ocr/tesseract,tesseract-ocr/tesseract,UB-Mannheim/tesseract,tesseract-ocr/tesseract,amitdo/tesseract,jbarlow83/tesseract,stweil/tesseract