BasicAuthenticationClient now takes python dictionary, instead of Config...

... object. More consistent with java version of auth client, and this also more easily enables users to work with other types of authentication clients (doesn't require them to create a new Config class for a different type of AuthenticationClient. Config.py was basically a restricted dictionary.
Do we have a test case where the auth client is instantiated, isAuthEnabled() function is called, and then configure() is called?