Support --json flag in all CLI commands

[Andarist]

Expected behavior:

npm support this for most of their commands which makes it way easier to depend on the stdout output without custom parsing etc. I've found places in the code where args are forwarded to npm but the result is often ignored and not returned to the caller - apart from those places there are also a lot of custom (or with custom implementations) commands that would benefit from this.

This should include returning thrown errors as jsons as well.

Actual behavior:

--json has no effect