Enforce Trusted/Approved and passing tests option

It would be very helpful from a peace-of-mind standpoint to enable a config option to allow choco list, install, & update to enforce approved, trusted-only and test-passing-only packages, otherwise show a message that describes the case.

Begin by locating the choco list, install, and update command entry points and the existing configuration handling. Define how the option applies consistently to approved, trusted-only, and test-passing-only packages; done means the commands enforce those checks and show a message describing the case when a package does not qualify.

Written by the indexing model from the issue text.