message: Skip installing ZMQhistViewer target with no X11
diff: @@ -139,6 +139,7 @@ if(ZEROMQ_FOUND)
  if (X11_FOUND)
  add_executable(ZMQhistViewer ZMQhistViewer.cxx)
  target_link_libraries(ZMQhistViewer HLTbase AliHLTGlobal AliZMQhelpers AliHLTUtil RAWDatabase Geom Graf MathCore Net Tree EG Gpad Matrix Minuit Physics VMC Thread STEERBase XMLParser Graf3d RIO Hist Core Hist Rint X11)
  + install(TARGETS ZMQhistViewer RUNTIME DESTINATION bin)
  endif (X11_FOUND)
  add_executable(ZMQproxy ZMQproxy.cxx)
  target_link_libraries(ZMQproxy HLTbase AliHLTGlobal AliZMQhelpers RAWDatabase Geom Graf MathCore Net Tree EG Gpad Matrix Minuit Physics VMC Thread STEERBase XMLParser Graf3d RIO Hist Core)
  @@ -148,6 +149,6 @@ if(ZEROMQ_FOUND)
  target_link_libraries(ZMQexample HLTbase AliHLTGlobal AliZMQhelpers RAWDatabase Geom Graf MathCore Net Tree EG Gpad Matrix Minuit Physics VMC Thread STEERBase XMLParser Graf3d RIO Hist Core)
  # Installation of
  - install(TARGETS ZMQexample ZMQfileProxy ZMQROOTmerger ZMQhistSource ZMQhistViewer ZMQproxy ZMQHLTchain RUNTIME DESTINATION bin)
  + install(TARGETS ZMQexample ZMQfileProxy ZMQROOTmerger ZMQhistSource ZMQproxy ZMQHLTchain RUNTIME DESTINATION bin)
  install(PROGRAMS ZMQmonitor.py o2header.py DESTINATION bin)
  endif(ZEROMQ_FOUND)
  