Issue description:

World crash when autocrafter trying to place a wither skull

What happens:

Game crashes

What you expected to happen:

Wither to be created ;)

Steps to reproduce:

1. set up a wither creator
2. link with network card
3. try to create wither ;)
   ...

Version (Make sure you are on the latest version before reporting):

• Minecraft: 1.10.2
• Forge: 12.18.3.2221
• Refined Storage: 1.2.20

Does this issue occur on a server? [yes/no]
no

If a (crash)log is relevant for this issue, link it here:

http://pastebin.com/nX75Xg45

[pastebin/gist/etc link here]

I went back to 12.2.18 and could start the world again and the wither was created with no problem.

Duplicate of #958