09-mar-2004 NvE Additional memberfunction AliObjMatrix::RemoveObject renamed to RemoveObjects to prevent
confusion and ambiguity in usage.
Linking facility of AliSignal extended by enabling multiple links to a specific signal slot.
Also call to AliSignal::ResetLink changed to AliSignal::ResetLinks() in the dtor
of AliTrack to adopt the extended AliSignal linking facility and output in
AliTrack::ListAll() limited to only the referring signal slots to prevent long output lists.