Update import location for mesh

nameserver/nameserver_test.go

@@ -10,8 +10,8 @@ import (
 	"time"
 
 	"github.com/stretchr/testify/require"
+	"github.com/weaveworks/mesh"
 
-	"github.com/weaveworks/weave/mesh"
 	"github.com/weaveworks/weave/net/address"
 	"github.com/weaveworks/weave/testing/gossip"
 )