Now there's just CHttpRequest::set_url(URL), no need to specify the
host, port and path manually anymore.
Updated ChanViewer and Downloader for the API change.
This broke due to a change in JsonValue API. JsonValue::to_string() now
returns the value serialized to a string, which may become "undefined".
You kinda want JsonValue::as_string(), but that is only callable when
the JsonValue *is* a string. Thankfully there is now as_string_or(alt).