Issue description:

What happens:

Empty pattern can be inserted into crafter

What you expected to happen:

Block that action

Steps to reproduce:

1. Craft a 10 pattern
2. Leave them in blank
3. Shift right click them into the crafter
4. Ta! Da!

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

• Minecraft: 1.10.2
• Forge: 12.18.2.2099
• Refined Storage: 1.2-beta4