Clear Patch for OpenMesh.. free all used memory on mesh clear

git-svn-id: http://www.openmesh.org/svnrepo/OpenMesh/trunk@190 fdac6126-5c0c-442c-9429-916003d36597

src/OpenMesh/Core/Utils/BaseProperty.hh

@@ -97,6 +97,9 @@ public: // synchronized array interface
   /// Resize storage to hold n elements.
   virtual void resize(size_t _n) = 0;
 
+  /// Clear all elements and free memory.
+  virtual void clear() = 0;
+
   /// Extend the number of elements by one.
   virtual void push_back() = 0;