Add a Screened status to product reviews to assist in moderation

I have decided to move this feature into a moderation submodule since it might be needed or desired by all users of this module.

Ran into an issue where the install hook ran before the view was created (installing both modules at the same time) and ended up with a view with nothing but the install hook contents (a broken view) and the module failing to install the screened table column so trying uninstall the moderation module failed.

The install hook is running too early and is running even if the config item doesn't exist yet.