fix a bug in dealing with a covariance matrix when fixed parameters are present  The size of the matrix is given by the number of free parameters
fix a bug in dealing with a covariance matrix when fixed parameters are present 
The size of the matrix is given by the number of free parameters


git-svn-id: ecbadac9c76e8cf640a0bca86f6bd796c98521e3@28711 27541ba8-7e3a-0410-8455-c3a389f83636

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