Make the Cookbook Checker script spit out more useful information

[digitaldogsbody]

Currently the CI for the cookbook script a) fails immediately after the first error, and b) doesn't output the actual error with the particular bit of code.

A is an easy fix, because I already wrote in a --fail-fast option, and we can just take that out
B requires a bit of thinking, because it happens due to a limitation of the way we run the scripts. It might be as simple as catching/printing STDERR.

At the same time, we should probably enable a better printing of success messages, rather than just silently returning with a 0 exit code, as positive affirmation is better for logs (and what actual testing tools do). Probably the best way to do this is to add that behaviour as default, and allow it to be disabled with a --silent flag.