acute and crop additions
acute and crop additions

- try to make window size to 0 in acute function to cover more if statements
- read mask in as non-grayscale image to try to cover more if statements

stiphyMT/plantcv,stiphyMT/plantcv,danforthcenter/plantcv,danforthcenter/plantcv,stiphyMT/plantcv,danforthcenter/plantcv