Split file into lines

        return dict with line=input, depth=n

def generate_lines(self, infile):
        """ Split file into lines

        return dict with line=input, depth=n
        """
        pound = '#'
        
        for line in infile:

            heading = 0

            if line.startswith(pound):
                heading = self.hash_count(line)

            yield dict(line=line, heading=heading)