glide: sync with etcd master
glide: sync with etcd master

Signed-off-by: Gyu-Ho Lee <3454051ee3341eb69bdf6fca40899cdad4d86496@gmail.com>

gyuho/etcdlabs,gyuho/etcdlabs,gyuho/etcdlabs,gyuho/etcdlabs,gyuho/etcdlabs