help: Fixup wording on password expiration policy

include/i18n/en_US/help/tips/settings.system.yaml

@@ -65,15 +65,16 @@ name_format:
     title: Default Name Format
     content: >
         Formatting technique used to format names throughout the system.
-        Email templates will use the format for names of no other format is
+        Email templates will use the format for names if no other format is
         specified in the place holder.
 
 # Authentication settings
 password_reset:
     title: Password Expiration Policy
     content: >
-        Sets the requirement for how often (in months) staff will be
-        required to reset their password.
+        Sets how often (in months) staff members will be required to change
+        their password. If disabled (set to "No expiration"), passwords will
+        not expire.
 
 # Date and time options
 date_and_time:

include/staff/settings-system.inc.php

@@ -123,10 +123,10 @@ $gmtime = Misc::gmtime();
                 <em><b>Authentication Settings</b></em>
             </th>
         </tr>
-        <tr><td>Password Change Policy:</th>
+        <tr><td>Password Expiration Policy:</th>
             <td>
                 <select name="passwd_reset_period">
-                   <option value="0"> &mdash; None &mdash;</option>
+                   <option value="0"> &mdash; No expiration &mdash;</option>
                   <?php
                     for ($i = 1; $i <= 12; $i++) {
                         echo sprintf('<option value="%d" %s>%s%s</option>',