* optimize cgroups settings for node reserved
* fix
* set cgroup slice for multi container engine
* set cgroup slice for crio
* add reserved cgroups variables to sample files
* Compatible with cgroup path for different container managers
* add cgroups doc
* fix markdown
* Containerd: download containerd from upstream instead of using distro specific packages
split runc download to separate role
make bootstrap-os role deploy container-selinux and seccomp libraries
clean up package manager provided containerd
move variables to docker role that are no longer common with containerd
* Containerd: make molecule testing more relevant
* replace ubuntu18 with ubuntu20
* add centos8 and debian11 to molecule tests
* run kubernetes/preinstall role to ensure relevancy
of test including dependency packages
* CI: adjust test scenarios for downloaded containerd