Add tests for util functions.
Add tests for util functions.

* tokenize_nl()
* extract_filter()
* resolve_tilde()
* quote_for_stfl()
* get_auth_method()
* get_proxy_type()

newsboat/newsboat,der-lyse/newsboat,newsboat/newsboat,newsboat/newsboat,der-lyse/newsboat,newsboat/newsboat,der-lyse/newsboat,newsboat/newsboat,newsboat/newsboat,der-lyse/newsboat,newsboat/newsboat,der-lyse/newsboat,der-lyse/newsboat,newsboat/newsboat,der-lyse/newsboat,der-lyse/newsboat