Mention the versions.xml help page in the intro page list.

common/content/dactyl.js

@@ -628,6 +628,7 @@ var Dactyl = Module("dactyl", XPCOM(Ci.nsISupportsWeakReference, ModuleBase), {
             // Manually process main and overlay files, since XSLTProcessor and
             // XMLHttpRequest don't allow access to chrome documents.
             tagMap["all"] = tagMap["all.xml"] = "all";
+            tagMap["versions"] = tagMap["versions.xml"] = "versions";
             let files = findHelpFile("all").map(function (doc)
                     [f.value for (f in util.evaluateXPath("//dactyl:include/@href", doc))]);
 

common/tests/functional/testHelpCommands.js

@@ -17,7 +17,8 @@ var setupTest = function (test) {
 const HELP_FILES = ["all", "tutorial", "intro", "starting", "browsing",
     "buffer", "cmdline", "insert", "options", "pattern", "tabs", "hints",
     "map", "eval", "marks", "repeat", "autocommands", "print", "gui",
-    "styling", "message", "developer", "various", "faq", "index", "plugins"];
+    "styling", "message", "developer", "various", "plugins", "faq", "versions",
+    "index"];
 
 var testViHelpCommand_OpensIntroHelpPage = function () {
     assertHelpOpensPageWithTag({

pentadactyl/locale/en-US/intro.xml

@@ -110,6 +110,11 @@
         <link topic="faq">FAQ</link>:
         Frequently asked questions.
     </li>
+    <li>
+        <link topic="versions">Version information</link>:
+        A detailed list of differences between each of the released versions of
+        &dactyl.appName;.
+    </li>
     <li>
         <link topic="index">Index</link>:
         An index of all commands and options.