Added a check to the destructor of Referenced so that it detects referenced

objects that are deleted whilest still having a positive _refCount, such
as when a object has been deleted on the stack, yet other references still
exist for it.  Have put the desctructor implementation in Object.cpp to
avoid adding yet another file with only a couple of lines of code in.

include/osg/Referenced

@@ -6,7 +6,6 @@
 #define OSG_REFERENCED 1
 
 #include <osg/Export>
-#include <set>
 
 namespace osg {
 
@@ -32,7 +31,7 @@ class SG_EXPORT Referenced
         inline const int referenceCount() const { return _refCount; }
 
     protected:
-        virtual ~Referenced() {}
+        virtual ~Referenced();
         mutable int _refCount;
 
 };

src/osg/Object.cpp

@@ -1,6 +1,18 @@
 #include <osg/Object>
+#include <osg/Notify>
+#include <typeinfo>
 
 using namespace osg;
 
+Referenced::~Referenced()
+{
+    if (_refCount>0)
+    {
+        notify(WARN)<<"Warning: deleting still referenced object "<<this<<" of type '"<<typeid(this).name()<<"'"<<std::endl;
+        notify(WARN)<<"         the final reference count was "<<_refCount<<", memory corruption possible."<<std::endl;
+    }
+}
+
+
 Object::Object(const Object&,const CopyOp&): 
     Referenced() {}