Automatic merge from submit-queue
First pass at CRI stream server library implementation
This is a first pass at implementing a library for serving attach/exec/portforward calls from a CRI shim process as discussed in [CRI Streaming Requests](https://docs.google.com/document/d/1OE_QoInPlVCK9rMAx9aybRmgFiVjHpJCHI9LrfdNM_s/edit#).
Remaining library work:
- implement authn/z
- implement `stayUp=false`, a.k.a. auto-stop the server once all connections are closed
/cc @kubernetes/sig-node