The docker service provided by the containers-basic bundle is masked
in ClearLinux distribution. This is causing errors in the following
steps. This commit ensures that the unit is not masked.
* bootstrap: rework role
* support being called from a non-root user
* run some commands in check mode
* unify spelling/task names
* bootstrap: fix wording of comments for check_mode: false
* bootstrap: remove setup-pipelining task
