code: def sleuthify_sailfish(sailfish_dir):
      
      if not R_package_path("wasabi"):
          return None
      else:
          rscript = Rscript_cmd()
          cmd = """{rscript} --no-environ -e 'library("wasabi"); prepare_fish_for_sleuth(c("{sailfish_dir}"))'"""
          do.run(cmd.format(**locals()), "Converting Sailfish to Sleuth format.")
      return os.path.join(sailfish_dir, "abundance.h5")
docs: if installed, use wasabi to create abundance.h5 output for use with
      sleuth