Added some preliminary Story and StoryGoal loading

-Moved the evaluation of story values from the story class to the
Evaluator class
-Added Story goal loading with some features:
--name, story value changes, and person lists which can satisfy the
changes
-Added story loading with some features
--preconditions, story value changes, and lists of a,b,c as well as the
chosen version of each of these. The chosen have no way of being chosen
-Evaluator returns the number of true conditions from the given list