Integrated VPN client: Add option for group name shared secret / group password

I have to use Cisco AnyConnect for some work-related VPNs because this option is not supported.

Another report, not by me:

https://social.technet.microsoft.com/Forums/ie/en-US/ccbfedbd-ace8-40c7-ad5f-68184ac10feb/windows-10-vpn-add-group-name-secret-password