Added a new base converter, IsolatedStorage extension method, amended ANID for WP8

Added the BooleanToValueBaseConverter which can be used by anyone to create new converters that depend on a true/false situation. Changed the existing filters of these nature to use it.

Added the IsolatedStorageFile extension method that will allow you to delete a folder, even if it's not empty.

Changed the UserExtendedPropertiesService implementation to use ANID2 for WP8 as ANID is now deprecated in phone 8.