Add missing files

src/main/java/exopandora/worldhandler/util/BlockPlacingMode.java

@@ -0,0 +1,14 @@
+package exopandora.worldhandler.util;
+
+public enum BlockPlacingMode
+{
+	KEEP,
+	REPLACE,
+	DESTROY;
+	
+	@Override
+	public String toString()
+	{
+		return this.name().toLowerCase();
+	}
+}

src/main/java/exopandora/worldhandler/util/Util.java

@@ -0,0 +1,39 @@
+package exopandora.worldhandler.util;
+
+import javax.annotation.Nullable;
+
+public class Util
+{
+	@Nullable
+	public static String serializeBounds(@Nullable Number minBound, @Nullable Number maxBound)
+	{
+		boolean min = minBound != null;
+		boolean max = maxBound != null;
+		
+		if(min && max && minBound.equals(maxBound))
+		{
+			return minBound.toString();
+		}
+		
+		if(min || max)
+		{
+			StringBuilder builder = new StringBuilder();
+			
+			if(min)
+			{
+				builder.append(minBound);
+			}
+			
+			builder.append("..");
+			
+			if(max)
+			{
+				builder.append(maxBound);
+			}
+			
+			return builder.toString();
+		}
+		
+		return null;
+	}
+}