Adds Skub (#740)

* Added Skub

* Added Skub crafting recipe

Resources/Prototypes/Construction/misc.yml

@@ -0,0 +1,12 @@
+- type: construction
+  name: Skub
+  id: skub
+  category: Items/Misc
+  keywords: [misc]
+  description: In the end, there is only Skub.
+  icon: Objects/Misc/skub.rsi/icon.png
+  result: Skub
+  objecttype: Item
+  steps:
+  - material: Metal
+    amount: 1

Resources/Prototypes/Construction/structures.yml

@@ -25,7 +25,7 @@
   name: Table
   id: table
   category: Structures
-  icon: 
+  icon:
     sprite: Buildings/table_solid.rsi
     state: plain_preview
   result: table