Miss some blocks in pre flattening mapping
I just saw that I miss some blocks in the 17w46a mappings. I added some missing ones in 36548e90. I realized, that some blocks seem to appear "twice". Compare "smooth_cobblestone" (43:11) and cobblestone. Exactly the same, but as a stair. How should we implement it?
Also an issue:
- Double slabs (+8)
- Leaves (+8)
See https://minecraft-de.gamepedia.com/Metadaten and https://minecraft-de.gamepedia.com/Numerische_Identifikation