Changes

I will leave comments in the Diff in regards to other parts I just disagree with.
I definitely prefer `if`, but most importantly, I prefer to express the condition as positively as possible.

This puts the least positive case first, which I don't like.
```ruby
if bob.age < 18
  site.deny_entry
else
  site.allow_entry
end
```

Naturally, it's super contrived and you could flip the comparator, but when using `unless` would allow the most positive expression, I use that.