added ROOT_EXECUTABLE variable
added ROOT_EXECUTABLE variable

petricm/LCIO,petricm/LCIO,iLCSoft/LCIO,petricm/LCIO,iLCSoft/LCIO,petricm/LCIO,iLCSoft/LCIO,iLCSoft/LCIO,petricm/LCIO,iLCSoft/LCIO,petricm/LCIO,iLCSoft/LCIO