alias for pack_into. has more up to date kwargs

def packstr(instr, textwidth=160, breakchars=' ', break_words=True,
            newline_prefix='', indentation='', nlprefix=None, wordsep=' ',
            remove_newlines=True):
    """ alias for pack_into. has more up to date kwargs """
    if not isinstance(instr, six.string_types):
        instr = repr(instr)
    if nlprefix is not None:
        newline_prefix = nlprefix
    str_ = pack_into(instr, textwidth, breakchars, break_words, newline_prefix,
                     wordsep, remove_newlines)
    if indentation != '':
        str_ = indent(str_, indentation)
    return str_