Update the vendor folder (#53)

* Update the vendor folder

* Update the Gopkg.lock by running dep ensure

vendor/github.com/opencontainers/runc/libcontainer/configs/cgroup_windows.go

@@ -0,0 +1,6 @@
+package configs
+
+// TODO Windows: This can ultimately be entirely factored out on Windows as
+// cgroups are a Unix-specific construct.
+type Cgroup struct {
+}