Nushell: `nu` should have a mode like `bash -c`

[mb21]

Original: "nu could read command so it could serve as a jq replacement"

Change usage to:

nu [OPTIONS] [COMMAND]

so you could do:

nu 'open https://api.github.com/repos/stedolan/jq/commits | first 1 | to-json'

This could make nu a viable replacement for jq so nu could sneak itself into bash scripts etc. that currently use jq. The equivalent jq command to the above is:

 curl https://api.github.com/repos/stedolan/jq/commits | jq '.[0]'

Care would have to be taken to pipe the stdin and stdout correctly.

[wycats]

This makes a lot of sense to me. We could just make it -c like bash, but I bet there's gotchas about how bash -c works that we'd want to avoid.

[jonathandturner]

We support nu -c now, closing