Added some prototype asteroid gen code

src/main/java/cr0s/warpdrive/config/structures/Asteroid.java

@@ -0,0 +1,20 @@
+package cr0s.warpdrive.config.structures;
+
+import org.w3c.dom.Element;
+
+import cr0s.warpdrive.config.InvalidXmlException;
+
+public class Asteroid extends Orb {
+
+	public Asteroid(int diameter) {
+		super(diameter);
+	}
+
+	@Override
+	public void loadFromXmlElement(Element e) throws InvalidXmlException {
+
+		super.loadFromXmlElement(e);
+
+	}
+
+}

src/main/resources/config/structures-default.xml

@@ -52,5 +52,13 @@
             <filler ratio=".5" block="minecraft:air" />
         </shell>
     </structure>
-
+    
+    <structure group="asteroid" name="asteroid" coreBlock="minecraft:iron_block" maxCoreSize="10" minCoreSize="2">
+        
+        <shell name="mantle" minThickness="3" maxThickness="20" fillerSets="commonOres;uncommonOres">
+            <filler weight="10" block="minecraft:stone" />
+            <filler weight="5" block="minecraft:cobblestone" />
+        </shell>
+        
+     </structure>
 </warpdriveWorldGeneration>