Added error for duplicated entries on address list.
Added error for duplicated entries on address list.

StCyr/otrs,mburggraf/otrs,oiami/otrs,linearregression/otrs,crythias/otrs,mburggraf/otrs,StCyr/otrs,mburggraf/otrs,brandonshults01/otrs,rudy500/otrs,muehlbauer/otrs,noritnk/otrs,moritz/otrs,s7design/otrs,brandonshults01/otrs,s7design/otrs,eliasp/otrs,balazj/otrs,rudy500/otrs,StCyr/otrs,s7design/otrs,xhoy/otrs,thorsteneckel/otrs,PortgasDAce/otrs,MBRG/otrs,muehlbauer/otrs,eliasp/otrs,eliasp/otrs,linearregression/otrs,oiami/otrs,crythias/otrs,nilei/otrs,PortgasDAce/otrs,thorsteneckel/otrs,s7design/otrs,s7design/otrs,StCyr/otrs,mburggraf/otrs,linearregression/otrs,brandonshults01/otrs,mbeijen/otrs-1,muehlbauer/otrs,rudy500/otrs,balazj/otrs,crythias/otrs,MBRG/otrs,nilei/otrs,moritz/otrs,brandonshults01/otrs,capeit-tto/otrs,capeit-tto/otrs,mbeijen/otrs-1,thorsteneckel/otrs,nilei/otrs,brandonshults01/otrs,xhoy/otrs,capeit-tto/otrs,rudy500/otrs,xhoy/otrs,noritnk/otrs,oiami/otrs,oiami/otrs,moritz/otrs,thorsteneckel/otrs,moritz/otrs,balazj/otrs,thorsteneckel/otrs,oiami/otrs,crythias/otrs,xhoy/otrs,nilei/otrs,linearregression/otrs,crythias/otrs,vlascoder/otrs,nilei/otrs,vlascoder/otrs,muehlbauer/otrs,vlascoder/otrs,PortgasDAce/otrs,muehlbauer/otrs,balazj/otrs,StCyr/otrs,linearregression/otrs,moritz/otrs,MBRG/otrs,mbeijen/otrs-1,PortgasDAce/otrs,eliasp/otrs,mburggraf/otrs,balazj/otrs,PortgasDAce/otrs,noritnk/otrs,MBRG/otrs,MBRG/otrs,xhoy/otrs,rudy500/otrs,eliasp/otrs