- use proper version comparison to avoid surprises, when alnum comparison leads to different results
- follow documentation conventions
- moved util_link_responding_p and util_get_http_status to
  http-client-procs and based it on util::http::*.
- marked util_link_responding_p and util_get_http_status as
  deprecated, moved a new version into the util::* namespace
  and turned positional arguments into non-positional