Currently it supports only `service start <SERVICE>`, but it could grow e.g.
`stop`, `exec` etc in the future (although you can still use `ctr` for those).
In order to be able to use go-compile.sh the containerd build needs to move
from /root/go to /go as the GOPATH.
The vendoring situation is not ideal, but since this tool wants to be an exact
match for the containerd it seems tollerable to reuse its vendoring.
Signed-off-by: Ian Campbell <ian.campbell@docker.com>