* Fix vyos on network_cli on python3
bytes do not have format() in Python3
* Push connection to tasks, with bonus connection=local test
* Run tests without explicit connection set
* Add/update START messages where appropriate
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.
