`docker{,-rootful}.yaml`: Use param in docker templates

[norio-nomura]

based on #2498

• docker.yaml: add .param.CONTAINERD_IMAGE_STORE
  By passing the --set .param.CONTAINERD_IMAGE_STORE=true option to limactl {create,start,edit}, the .features."containerd-snapshotter" option will be enabled in docker/daemon.json inside the VM.
• docker.yaml: add .param.ROOTFUL
  By passing the --set .param.ROOTFUL=true option to limactl {create,start,edit}, Docker inside the VM will run in rootful mode.
• docker-rootful.yaml: make everything common except for setting .param.ROOTFUL=true in docker.yaml.

Thanks,