Add nsenter details to libcontainer README.md
Add the import of nsenter to the example in libcontainer's README.md, as without it none of the example code works.
@@ -16,7 +16,14 @@ the current binary (/proc/self/exe) to be executed as the init process, and use
arg "init", we call the first step process "bootstrap", so you always need a "init"
function as the entry of "bootstrap".
+In addition to the go init function the early stage bootstrap is handled by importing
+[nsenter](https://github.com/opencontainers/runc/blob/master/libcontainer/nsenter/README.md).
+
```go
+import (
+ _ "github.com/opencontainers/runc/libcontainer/nsenter"
+)
+
func init() {
if len(os.Args) > 1 && os.Args[1] == "init" {
runtime.GOMAXPROCS(1)
