fix check of the labels when using Divide or Multiply and print a warning message when one of the two histogram has not labels, while the other has labels
fix check of the labels when using Divide or Multiply and print a warning message when one of the two histogram has not labels, while the other has labels


git-svn-id: acec3fd5b7ea1eb9e79d6329d318e8118ee2e14f@44965 27541ba8-7e3a-0410-8455-c3a389f83636

bbockelm/root-historical,bbockelm/root-historical,bbockelm/root-historical,bbockelm/root-historical,bbockelm/root-historical,bbockelm/root-historical,bbockelm/root-historical