hush: straighten parse_stream() API a bit

function                                             old     new   delta
parse_stream                                        1240    1238      -2
expand_variables                                    2272    2242     -30
parse_and_run_stream                                 338     292     -46
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(add/remove: 0/0 grow/shrink: 0/3 up/down: 0/-78)             Total: -78 bytes

1 file changed