Created a pretty reporter

This is a simplified reporter from #283 
`equal` is OK in these cases since nothing other than a string could be represented by `mockCharm.out` and still pass, but just for future reference, just like with `===` in code, it’s preferred to use `strictEqual` to avoid edge cases/scenarios where a type accidentally changes in code but the coerced value stays the same so the test passes even though the code changed incorrectly.