added virtual destructor to the csRefCounter baseclass so the right destructor in DecRef is called
added virtual destructor to the csRefCounter baseclass so the right destructor in DecRef is called


git-svn-id: 28d9401aa571d5108e51b194aae6f24ca5964c06@11608 8cc4aa7f-3514-0410-904f-f2cc9021211c

crystalspace/CS,crystalspace/CS,crystalspace/CS,crystalspace/CS,crystalspace/CS,crystalspace/CS,crystalspace/CS,crystalspace/CS