Dynamic configuration / CLI

[mcandre]

Would be great to expose command line argument configuration to CloudABI processes, so that more dynamic configuration can be used. For example, a CloudABI-enabled ls would want to be able to accept file paths. A CloudABI-enabled nc would want to accept port numbers.

As a workaround, users can write wrapper scripts to generate different cloudabi YAML configurations based on the CLI arguments. But it would be much better to have cloudlibc and cloudabi-utils provide this out of the box!