hush: fix set [--] params. Closes bug 199.

function                                             old     new   delta
builtin_set                                           55     194    +139
add_strings_to_strings                                 -     130    +130
add_string_to_strings                                110      26     -84
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(add/remove: 1/0 grow/shrink: 1/1 up/down: 269/-84)           Total: 185 bytes

1 file changed