CrozzWord stores locally
* preferences
* saved puzzles
* cached site categories (for Registered users)

RemoveAll:
* resets preferences to original default values
* reclaims space, e.g., rarely used categories
* cleans up if uninstaller fails to remove CrozzWord's "record stores"

CrozzWord re-creates these as needed after it starts up/runs

RemoveAll: confirms and exits