Fix: Add missing getter functions

CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/datastructure/BuildingUnit.java

@@ -126,4 +126,8 @@ public class BuildingUnit extends AbstractBuildingSubdivision {
         }
         this.abs = originalBu.abs;
     }
+
+    public List<Storey> getStoreys() {
+        return storeys;
+    }
 }

CityDoctorParent/CityDoctorModel/src/main/java/de/hft/stuttgart/citydoctor2/datastructure/Storey.java

@@ -125,4 +125,8 @@ public class Storey extends AbstractBuildingSubdivision {
         }
         this.abs = originalSt.abs;
     }
+
+    public List<BuildingUnit> getBuildingUnits() {
+        return buildingUnits;
+    }
 }