UUID Migration Rework, Bug Fixes

Using multi-faceted strategy to better resolve UUIDs, and do it faster.
Fixed dispensers putting fluids in a neighboring claim.
Automatically deleting claims for worlds which no longer exist.
Streamlined visualization code, hopefully will reduce or eliminate weird
visualizations for VERY big land claims.
Removed option to disallow un-claiming land in creative mode.
Better default for last login date for new players or players who've had
their data deleted or lost.
Version to 8.2.2