I&F: RLCraft Edition

Fixes an issue with certain generated dread blocks (stone faces & slabs) being breakable in some cases. Mausoleums utilize dread stone faces, so this fix prevents the player from breaking into a mausoleum with a pickaxe.

Dread Stone Slabs, on the other hand, did not behave as regular dread blocks - making them always breakable. Dread Stone Stairs are still breakable, but solving this issue for the stairs would require the creation of a new un-craftable stairs block.