Progress on Implementing Dungeon Packs

1. Integrated support for dungeon pack config options into the code
(i.e. we actually DO what the settings specify)
2. Added random transitions from one dungeon type to another. Dungeons
might also begin with a non-default pack.
3. Fixed a config reading bug that caused settings to be ignored and
some invalid settings wouldn't trigger exceptions. Also fixed other
dungeon pack bugs.

StevenDimDoors/mod_pocketDim/dungeon/pack/DungeonChainRuleDefinition.java

@@ -11,6 +11,25 @@ public class DungeonChainRuleDefinition
 	
 	public DungeonChainRuleDefinition(ArrayList<String> conditions, ArrayList<WeightedContainer<String>> products)
 	{
+		//Validate the arguments, just in case
+		if (conditions == null)
+		{
+			throw new NullPointerException("conditions cannot be null");
+		}
+		if (products.isEmpty())
+		{
+			throw new IllegalArgumentException("products cannot be an empty list");
+		}
+		for (WeightedContainer<String> product : products)
+		{
+			//Check for weights less than 1. Those could cause Minecraft's random selection algorithm to throw an exception.
+			//At the very least, they're useless values.
+			if (product.itemWeight < 1)
+			{
+				throw new IllegalArgumentException("products cannot contain items with weights less than 1");
+			}
+		}
+		
 		this.conditions = conditions;
 		this.products = products;
 	}