* Use vars for user, group and locale suffix.
* Switch tests from `es_MX` to `es_ES`.
* Enable postgresql tests on freebsd.
* Work-arounds for service restart on freebsd.
This change corrects problems reported by the `yamllint` linter.
Since key duplication problems were removed in 4d48711, this commit
mainly fixes trailing spaces and extra empty lines at beginning/end of
files.