This changes the shim's OOM score from a static max killable of -999 to
be +1 of the containerd daemon's score. This should allow the shim's to
be killed first in an OOM condition but leave the daemon alone for a bit
to help cleanup and manage the containers during this situation.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
Shims no longer call `os.Exit` but close the context on shutdown so that
events and other resources have hit the `defer`s.
Signed-off-by: Michael Crosby <crosbymichael@gmail.com>
