Add caret mode to help index.

common/locale/en-US/index.xml

@@ -26,6 +26,8 @@ This file contains a list of all available commands, mappings and options.
 
 <h2 tag="n-map-index">Normal mode</h2>
 
+<h2 tag="caret-map-index">Caret mode</h2>
+
 <h2 tag="v-map-index">Visual mode</h2>
 
 <h2 tag="c-map-index">Command-line editing</h2>

common/locale/en-US/various.xml

@@ -261,7 +261,7 @@
     <description>
         <p>
             Start Caret mode. This mode resembles Vim's Normal mode where the
-            text cursor is visible on the web page. The <k link="false">v</k>
+            text cursor is visible on the web page. The <k mode="caret">v</k>
             key enters Visual mode, where text is selected as the cursor moves.
         </p>
         <p>