Add BasicClient::new_non_authenticated()

[jn9e9]

To support parallaxsecond/parsec-tool#49 it is necessary to create a new BasicClient without authentication being automatically configured as it is with BasicClient::new().

It would be possible to use latest version of new_naked(), but this would not automatically configure other aspects of the client (e.g. providers).

New method should do all the auto configuration as BasicClient::new() except for authenticator, which should be set to Authentication::None