Object sense support / Bugfixes

core/src/mindustry/logic/Senseable.java

@@ -3,6 +3,12 @@ package mindustry.logic;
 import mindustry.ctype.*;
 
 public interface Senseable{
+    Object noSensed = new Object();
+
     double sense(LAccess sensor);
     double sense(Content content);
+
+    default Object senseObject(LAccess sensor){
+        return noSensed;
+    }
 }