Multiple voxel servers

- Added support to voxel server to support a "Jurisdiction" config file on command line, that tells it which portion of the voxel space it's responsible for.
- Added support to VoxelTree encoding to not send "missing bits" when tree is outside of jurisdiction
- Added support to client to display ping stats for multiple voxel serves
- Removed VOXEL_SERVER from SOLO_NODE_TYPES
- Added "False Color" support for voxels from different voxel server sources