overhauled registry

src/main/java/de/srsoftware/web4rail/tiles/DiagNE.java

@@ -3,6 +3,7 @@ package de.srsoftware.web4rail.tiles;
 import java.util.HashMap;
 import java.util.Map;
 
+import de.srsoftware.web4rail.BaseClass;
 import de.srsoftware.web4rail.Connector;
 import de.srsoftware.web4rail.Plan.Direction;
 import de.srsoftware.web4rail.tiles.Turnout.State;
@@ -21,4 +22,9 @@ public class DiagNE extends Tile{
 				return new HashMap<>();
 		}
 	}
+	
+	@Override
+	protected void removeChild(BaseClass child) {
+		// this class has no child elements		
+	}
 }