Describe the bug
Railgun Grenades need Steel Rods to craft, not Aluminium.

To Reproduce
Steps to reproduce the behavior:

1. Put core into Assembler
2. Try to put in Aluminium Rod; fails
3. Put in Treated Stick; produces regular Grenade
4. Put in Steel Rod; produces Railgun Grenade

Expected behavior
Either Aluminium Rods to work, or the manual to say Steel Rods

Environment

• OS: Linux
• Minecraft version: 1.12.2
• Forge version: 14.23.5.2855
• Immersive Intelligence version: 0.2.1
• Immersive Engineering version: 0.12-98
  If you have other mods installed, it would be nice if you send a list of them too (maybe it's not II's fault after all) ^^.

Since my pull request was added, this is now fixed.