* Lint everything in the repository with yamllint
* yamllint fixes: syntax fixes only
* yamllint fixes: move comments to play names
* yamllint fixes: indent comments in .gitlab-ci.yml file
* 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