Right now container runtimes have no way to provide additional context
to the pull errors. We now loosen the constraints and check for
additional messages after the actual CRI errors, which allows to enrich
the verbosity of the warning events, for example:
```
Warning Failed 2s (x3 over 43s) kubelet Failed to pull image "localhost:5000/foo": RegistryUnavailable: pinging container registry localhost:5000: Get "http://localhost:5000/v2/": dial tcp [::1]:5000: connect: connection refused
```
Signed-off-by: Sascha Grunert <sgrunert@redhat.com>
aa405c8aac