v4.3.0

Override options via CLI flags, environment variables, or rc file.

• authToken - set the auth token to use so that we don't run login code each time.
• apiUserAgent - override the default API user agent
• downloadUserAgent - override the default download user agent
• countryCode - set the country code e.g., for gp-details.
• language - set the language e.g., for gp-details