Using multiline shell variables in options

Using multiline variables works for commands, but not for options.

For instance, folding works:
```
$ foo="foo1
> foo2
> foo3"
$ cluset -f $foo
foo[1-3]
```

But it doesn't work when multiline variables are passed as options:
```
$ cluset -f foo[1-4] -x "$foo"
foo[1-4]
```
Expected result:
```
$ cluset -f foo[1-4] -x "$foo"
foo4
$ cluset -f foo[1-4] -x "foo[1-3]"
foo4
```
