incorrect UI description in README file

[bradbulger]

In the section labeled "INSTALLATION DRUPAL 8.x", there is a bullet item:

You are now presented with different actions you can perform within the group. Such as add group members, add roles, and set member permissions. You will notice that these options have the same look and feel as Drupal core in matters relating to management of roles and permissions.

None of that exists. It should, but until it does, at least remove or reword this.

[MPParsley]

Hi @bradbulger,

The documentation is still for Drupal 7. You are welcome to open a PR to update the documentation for Drupal 8.

See WIP on #231 & #243.

[bradbulger]

How can I update the documentation when I need to read documentation to understand how it works?