New feature for Cpp selection mechanism. If a class in the Cpp selection

namespace contains a member of type "NO_SELF_AUTOSELECT", then this class
will NOT be selected for dictionary generation (despite dictinaries for
any member types etc. in this class will be generated)


git-svn-id: http://root.cern.ch/svn/root/trunk@14727 27541ba8-7e3a-0410-8455-c3a389f83636