move dependencies to vendor

vendor/github.com/docker/libcontainer/stats.go

@@ -0,0 +1,15 @@
+package libcontainer
+
+type NetworkInterface struct {
+	// Name is the name of the network interface.
+	Name string
+
+	RxBytes   uint64
+	RxPackets uint64
+	RxErrors  uint64
+	RxDropped uint64
+	TxBytes   uint64
+	TxPackets uint64
+	TxErrors  uint64
+	TxDropped uint64
+}