change analysis_image in watershed
change analysis_image in watershed

- Removed the filename parameter from the watershed function
- Changed the function so it returns an image rather than a list with the name of the file.
- Function won't print out the image unless debug='print'

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