update libkv, fix wrong error check on zookeeper list

Signed-off-by: Alexandre Beslic <alexandre.beslic@gmail.com>

hack/vendor.sh

@@ -73,7 +73,7 @@ clone git github.com/hashicorp/go-msgpack 71c2886f5a673a35f909803f38ece581016509
 clone git github.com/hashicorp/memberlist 88ac4de0d1a0ca6def284b571342db3b777a4c37
 clone git github.com/hashicorp/go-multierror fcdddc395df1ddf4247c69bd436e84cfa0733f7e
 clone git github.com/hashicorp/serf 598c54895cc5a7b1a24a398d635e8c0ea0959870
-clone git github.com/docker/libkv 7283ef27ed32fe267388510a91709b307bb9942c
+clone git github.com/docker/libkv v0.2.1
 clone git github.com/vishvananda/netns 604eaf189ee867d8c147fafc28def2394e878d25
 clone git github.com/vishvananda/netlink 734d02c3e202f682c74b71314b2c61eec0170fd4
 clone git github.com/BurntSushi/toml f706d00e3de6abe700c994cdd545a1a4915af060

vendor/src/github.com/docker/libkv/.travis.yml

@@ -16,7 +16,7 @@ before_install:
 
 before_script:
   - script/travis_consul.sh 0.6.3
-  - script/travis_etcd.sh 2.2.5
+  - script/travis_etcd.sh 3.0.0
   - script/travis_zk.sh 3.5.1-alpha
 
 script:

vendor/src/github.com/docker/libkv/store/zookeeper/zookeeper.go

@@ -252,7 +252,7 @@ func (s *Zookeeper) List(directory string) ([]*store.KVPair, error) {
 		pair, err := s.Get(strings.TrimSuffix(directory, "/") + s.normalize(key))
 		if err != nil {
 			// If node is not found: List is out of date, retry
-			if err == zk.ErrNoNode {
+			if err == store.ErrKeyNotFound {
 				return s.List(directory)
 			}
 			return nil, err