Enable jaq to deal with non-UTF-8 file paths (on the command-line).

[01mf02]

This PR allows providing paths on the command-line that are not UTF-8, see #231.

To see this in action:

mkdir foo
echo bar > foo/$(iconv -f UTF-8 -t UTF-16 <(echo 'abc#$%%^'))
cargo run -- -n --rawfile a foo/* '$a'

This should yield "bar\n". Before this PR, this would fail with:

error: Invalid UTF-8 was detected in one or more arguments

[thaliaarchi]

You’ve got an unwrap in the case the filter isn’t valid UTF-8, by the way, which bypasses your error propagation.

[01mf02]

You’ve got an unwrap in the case the filter isn’t valid UTF-8, by the way, which bypasses your error propagation.

You're right, I got a bit lazy. e75ecbd addresses this now. Thanks for bringing it up.