When running tests with additional non-sws arguments, tests execution
fails because sws is trying to parse cli arguments anyways.

Now, sws won't parse arguments by default when running tests.
For example, the following command will work as expected:

cargo test -- --test-threads 1 --nocapture

Now boolean flags like --directory-listing, --compression_static, etc
will work in three variants.

For example:

--directory-listing
--directory-listing true
--directory-listing=true

…nabled (#471)