Persistence

After tearing down and rebuilding the Persistence code I've got some initial classes that save user preferences. Please take a look at these and let me know the areas in which they don't meet expectations. I originally committed (in the wrong branch, which can be removed) an interface for this. But it was an ugly mutt that married two desperate concepts: window placement and selected paths. I've disjoined these two and I think the result is cleaner and more logical. I spent way too much time trying to apply the teachings of the Java book instead of getting things done, but I welcome any and all suggestions of how I might better shape this code. Thanks for your patience everyone.