private void createGroups(final Namespace namespace) {
        final List<String> groups = extractStrings(namespace, CREATE_GROUP_ARG_NAME);
        groups.forEach(this::createGroup);
    }
Creates an account in the internal identity provider
<p>
e.g manage_users ../local.yml
--createUser admin
--createGroup Administrators
--addToGroup admin Administrators
--grantPermission Administrators Administrator
stroom-app/src/main/java/stroom/app/commands/ManageUsersCommand.java