Added virtual destructor to reader and writer classes in order to avoid compiler warnings.

git-svn-id: http://www.openmesh.org/svnrepo/OpenMesh/trunk@84 fdac6126-5c0c-442c-9429-916003d36597

Core/IO/writer/BaseWriter.hh

@@ -67,6 +67,9 @@ class BaseWriter
 public:
 
   typedef unsigned int Option;
+
+  /// Destructor
+  virtual ~BaseWriter() {};
    
   /// Return short description of the supported file format.
   virtual std::string get_description() const = 0;