Added an empty virtual destructor to AbstractNode which fixes the memory leaks from the compilers.
Added an empty virtual destructor to AbstractNode which fixes the memory leaks from the compilers.

--HG--
branch : v1-6

digimatic/ogre,digimatic/ogre,digimatic/ogre,digimatic/ogre,digimatic/ogre,digimatic/ogre,digimatic/ogre