Implemented Importing and Exporting Tile Entities; Additional Improvements

I implemented exporting tile entities in custom dungeons and importing tile entities through SchematicLoader. As far as I can tell, it works smoothly and it's fully compatible with MCedit. We no longer need JNBT in our code, so I removed the whole package and its classes. I also fixed a few bugs and improved how we export dungeons so we no longer need permafabric as a marker for the bounds of the dungeon.