* when resources are missing, fails gracefully
* uses highest found rating, rather than most recently found for the
case of sets containing duplicates
* moved ratings files to their own directory
* thread safe reading of all files
the way stored ratings for cards has been reworked
1. each set has its own ratings file and it will be loaded dynamically
if the AI needs it
2. each ratings file for a set is normalized within itself, so the
rating systems don't need to be scaled to match eachother. essentially
cards are rated within the context of their set
3. changed the rarity rating booster to only apply to unrated cards
4. the file setsWithRatings.csv explains how to add additional ratings.
no code changes are required, but a recompilation will be required to
add the files to the jar.
