The "Add New Users" plugin appears to contain code on line 480 that's incompatible with PHP7, the now-recommended PHP version for WordPress.
[02-Jan-2017 22:48:25 UTC] PHP Parse error: syntax error, unexpected 'new' (T_NEW) in /home/demo/sites/intranet/cms/assets/plugins/add-new-users/add-new-users.php on line 480
The line is
$add_new_users =& new Add_New_Users; but I think it should now just be
$add_new_users = new Add_New_Users;