Throw old DataExceptions in schematic related classes.

The schematic related classes are slated for deprecation at some point.

src/legacy/java/com/sk89q/worldedit/data/DataException.java

@@ -24,4 +24,11 @@ package com.sk89q.worldedit.data;
  */
 @Deprecated
 public class DataException extends com.sk89q.worldedit.world.DataException {
+
+    public DataException(String msg) {
+        super(msg);
+    }
+
+    public DataException() {
+    }
 }