corrected destructors

structure.cpp

@@ -19,7 +19,6 @@ namespace battleship{
 	Structure::~Structure(){
 		removeBar(buildStatusForeground);
 		removeBar(buildStatusBackground);
-		Unit::~Unit();
 	}
 
 	void Structure::update(){

unit.h

@@ -68,7 +68,7 @@ namespace battleship{
 		};
 
         Unit(Player*, int, vb01::Vector3, vb01::Quaternion);
-        ~Unit();
+        virtual ~Unit();
         virtual void update();
         virtual void blowUp();
         virtual void halt();

vehicle.cpp

@@ -29,8 +29,6 @@ namespace battleship{
 	Vehicle::~Vehicle(){
 		removeAllPathpoints();
 		delete debugMat;
-
-		Unit::~Unit();
 	}
 
 	void Vehicle::update(){