Add Item independent NBT saving for Liquids

This simple PR will allow users to add/remove mods that take advantage of the LiquidDictionary without the associated issues that currently plague the LiquidDictionary.

Typically users are forced to break all their pipes/tanks/machines to get rid of the old liquid item. With this change, that should no longer become necessary in most cases. Existing liquids will self-convert to the new liquid item on world save/load.

Of course this assumes that mods are actually using the LiquidStack nbt functions.

This change should be 100% backwards compatible and has been tested to work.