Make it optional to define protected custom variables

fixes #7590

modules/monitoring/application/forms/Config/SecurityConfigForm.php

@@ -55,7 +55,8 @@ class SecurityConfigForm extends ConfigForm
             'text',
             'protected_customvars',
             array(
-                'required'      => true,
+                'allowEmpty'    => true,
+                'value'         => '*pw*,*pass*,community',
                 'label'         => mt('monitoring', 'Protected Custom Variables'),
                 'description'   => mt('monitoring',
                     'Comma separated case insensitive list of protected custom variables.'

modules/monitoring/library/Monitoring/Installation/SecurityStep.php

@@ -56,7 +56,9 @@ class SecurityStep extends Step
             . '<tbody>'
             . '<tr>'
             . '<td><strong>' . mt('monitoring', 'Protected Custom Variables') . '</strong></td>'
-            . '<td>' . $this->data['securityConfig']['protected_customvars'] . '</td>'
+            . '<td>' . ($this->data['securityConfig']['protected_customvars'] ? (
+                $this->data['securityConfig']['protected_customvars']
+            ) : mt('monitoring', 'None', 'monitoring.protected_customvars')) . '</td>'
             . '</tr>'
             . '</tbody>'
             . '</table>';