Damage Calculator

The same calculator with some little fixes. Also implemented the suggestions.
The problem I ran into was that the JSON is inconsistent. The value of the key isViable is a boolean with false if it doesn't have a secondary effect and a description of the effect if it has one.
The JSONParser would throw an exception if it isn't a boolean which I am catching so the damage won't be 0.
The hasSecondary should be initialized with true though.