Research & document containerd integration

[akhramov]

In order to provide support for containerd, our implementation of runc needs to

• implement not only standard operations, but also additional, such as
  • exec
  • running in detached mode
• implement "containerd-shim", an interface for containerd.

The scope of this task is to

• document in free-form what has to be done in order to integrate with containerd
• document in free-form how to build containerd on FreeBSD
• document in free-form how containerd allocates network addresses for containers. Currently we set up networking right within runtime, but probably it should be done somehow else
• (optional) create a proof of concept of containerd-shim

[akhramov]

document in free-form what has to be done in order to integrate with containerd

#14

document in free-form how to build containerd on FreeBSD

Basically, containerd repo contains a GNU makefile. I had no problems with make build whatsoever.

document in free-form how containerd allocates network addresses for containers.

Networking is out of scope of containerd
https://github.com/containerd/containerd/blob/261c107ffc4ff681bc73988f64e3f60c32233b37/SCOPE.md#scope