Extend shortcuts list modal. Mention it at help page

app/views/help/_shortcuts.html.haml

@@ -12,3 +12,19 @@
       %span.label.label-inverse ?
       –
       Show this dialog
+
+    %h5 Project Files browsing
+    %p
+      %span.label.label-inverse
+        %i.icon-arrow-up
+      –
+      Move selection up
+    %p
+      %span.label.label-inverse
+        %i.icon-arrow-down
+      –
+      Move selection down
+    %p
+      %span.label.label-inverse Enter
+      –
+      Open selection

app/views/help/index.html.haml

@@ -24,6 +24,9 @@
           Use the
           = link_to "search bar", '#', onclick: "$('#search').focus();"
           on the top of this page
+        %li
+          Use
+          = link_to "shortcuts", '#', onclick: "new Shortcuts()"
         %li
           Ask in our
           = link_to "mailing list", "https://groups.google.com/forum/#!forum/gitlabhq"
@@ -32,6 +35,7 @@
         %li
           Browse our
           = link_to "issue tracker", "https://github.com/gitlabhq/gitlabhq/issues"
+
   .span4
     .ui-box
       .title