Fix NPE when rotating hanging entities (#356)

worldedit-core/src/main/java/com/sk89q/worldedit/function/entity/ExtentEntityCopy.java

@@ -158,12 +158,14 @@ public class ExtentEntityCopy implements EntityFunction {
                         Vector vector = transform.apply(direction.toVector()).subtract(transform.apply(Vector.ZERO)).normalize();
                         Direction newDirection = Direction.findClosest(vector, Flag.CARDINAL);
 
+                        if (newDirection != null) {
                             byte hangingByte = (byte) MCDirections.toHanging(newDirection);
                             builder.putByte("Direction", hangingByte);
                             builder.putByte("Facing", hangingByte);
                             builder.putByte("Dir", MCDirections.toLegacyHanging(MCDirections.toHanging(newDirection)));
                         }
                     }
+                }
 
                 return new BaseEntity(state.getTypeId(), builder.build());
             }