• crun: new command "crun features".
• linux: fix handling of idmapped mounts when the container joins an existing PID namespace.
• linux: support io_priority from the OCI specs.
• linux: handle correctly the case where the status file is not written yet for a container.
• crun: fix segfault for "ps" when the container is not using cgroups.
• cgroup: allow setting swap to 0.