Some testing of NBT format saving.
Test code.  This NBT api works, but is annoying.
And removed.
Further test code removal.
Importing mojang NBT code
This code is the same as that found in
https://mojang.com/2012/02/new-minecraft-map-format-anvil/ except that
the package was changed.
Changed log level to finest - Don't need that much logging.
NBT test code.  This time it works.
Added some NBT serialization code of IslandInfos.
Proper serialization, and a quick test of it.
Removed debug logging.
A quick test because my USkyblock source is broken.
Added newlines.

I have a weird screen size sometimes, so I try to cutoff at around 75.
Made nested classes static.
Added conversion of uSkyBlock classes - WIP, not functional due to
nulls.  
(PlayerInfo needs some checks to make sure things work)