Smelting and Stonecutting Slabs and Stairs

The ability to smelt and use the stonecutter on slabs and stairs. For example, lets say you have an excess of cobblestone slabs/stairs. With this feature, you could put them in a furnace to get stone slabs/stairs, and then you could put the slabs in the furnace again to get smooth stone slabs. Or you could put the stone slabs/stairs into the stonecutter in order to obtain stone brick slabs/stairs. You would also be able to smelt andesite, diorite and granite slabs/stairs into their respective polished versions.