code changes for pkgadd, validation function to support issu, nssu
code changes for pkgadd, validation function to support issu, nssu

pklimai/py-junos-eznc,pklimai/py-junos-eznc,spidercensus/py-junos-eznc,spidercensus/py-junos-eznc,Juniper/py-junos-eznc,spidercensus/py-junos-eznc,pklimai/py-junos-eznc,Juniper/py-junos-eznc,Juniper/py-junos-eznc