check admin and and webmaster group but NOT user member

[mtaipe]

In a scenario where all valid LDAP user are allowed so no need to specify an LDAP group (ld_group_user) and verify the users membership on it but have some of these users as admins or webmaster does not work because setting the variable ld_group_user_active to 0 to prevent verifying general users will also give everyone admin access regardless the variables ld_group_admin_active and ld_group_webmaster_active are set to 1 and the ld_group_admin and ld_group_webmaster have a correct group value.