update Dockerfile-gpu to support cudnn by updating symlink + ld_library_path
update Dockerfile-gpu to support cudnn by updating symlink + ld_library_path

niazangels/CADL,alvaroing12/CADL,goddoe/CADL,niazangels/CADL,padipadou/CADL,padipadou/CADL,goddoe/CADL,pkmital/CADL,pkmital/CADL,alvaroing12/CADL