Makes a subproduct filename by calling subproductPath(), then calls
        subproductUpToDate() to determine if it is up-to-date.
        Returns tuple of basename,path,uptodate

def subproduct(self, ext):
        """Makes a subproduct filename by calling subproductPath(), then calls
        subproductUpToDate() to determine if it is up-to-date.
        Returns tuple of basename,path,uptodate
        """
        fname, fpath = self.subproductPath(ext)
        return fname, fpath, self.subproductUpToDate(fpath)