Visualization for Voxel Server Add/Kill

When voxel servers are added or removed from the domain, the connected clients will animate a transparent cube over the region of the voxel server thats coming or going.

- added "jurisdiction" to the voxel scene stats so client knows what a server is responsible for
- added call back hooks to NodeList so any interested parties can be notified of changes
- kill local voxels when the voxel server goes away
- added VoxelFade class in interface which will fade in or fade out around a voxel specification
- added voxelDetailsForCode() which will convert an octcode into VoxelPositionSize details