From Philippe: When a new histogram has the same name as an existing one, the existing one is removed from the directory. This patch also set the fDirectory member to 0 for the existing histogram.
From Philippe:
When a new histogram has the same name as an existing one,
the existing one is removed from the directory.
This patch also set the fDirectory member to 0 for the existing histogram.


git-svn-id: ecbadac9c76e8cf640a0bca86f6bd796c98521e3@8356 27541ba8-7e3a-0410-8455-c3a389f83636

dawehner/root,bbannier/ROOT,dawehner/root,dawehner/root,bbannier/ROOT,dawehner/root,dawehner/root,dawehner/root,bbannier/ROOT,dawehner/root,bbannier/ROOT,bbannier/ROOT,dawehner/root,bbannier/ROOT,bbannier/ROOT