tweaks; checking empty rows when chaining; better grouping of contradictory values
tweaks; checking empty rows when chaining; better grouping of contradictory values

mitdbg/aurum-datadiscovery,mitdbg/aurum-datadiscovery,mitdbg/aurum-datadiscovery,mitdbg/aurum-datadiscovery,mitdbg/aurum-datadiscovery,mitdbg/aurum-datadiscovery