Add one-time-code to list of input purposes

guidelines/input-purposes.html

@@ -18,6 +18,7 @@ <h2>Input Purposes for User Interface Components</h2>
 		<li><code>username</code> - A username</li>
 		<li><code>new-password</code> - A new password (e.g., when creating an account or changing a password)</li>
 		<li><code>current-password</code> - The current password for the account identified by the <code>username</code> field (e.g., when logging in)</li>
+		<li><code>one-time-code</code> - 	One-time code used for verifying user identity</li>
 		<li><code>organization</code> - Company name corresponding to the person, address, or contact information in the other fields associated with this field</li>
 		<li><code>street-address</code> - Street address (multiple lines, newlines preserved)</li>
 		<li><code>address-line1</code> - Street address (one line per field, line 1)</li>