Fixed false failure bug, added noaction support

Fixed the problem where occasionally curl reported a failure (inspite of
using the option to prevent this) which caused ncm-download to
incorrectly report an error.

Modernised to include --noaction support. Component already had unit
tests in spite of using LC::Check::status. It turns out that
LC::Check::status *does* support noaction so is test safe.
I did consider this briefly (because it was so easy) but `$proc->{COMMAND}` creates a dependency on the underlying data structure. Where I come from that is known as a Bad Thing.

The whole point of building the temporary list was because the API could not supply the final command.