Initialize performs the first sync of the firewall rule.

List prints out the current source IPs configured in ~/.bitly_firewall and the source IPs active on the GCP Firewall.

Sync initiates a manual synchronization of the local configuration stored in ~/.bitly_firewall to the desired GCP Firewall.

Update will intelligently update the firewall rule if the user's public IP has changed and doesn't exist in the current rule.