Add new category "Guides" to the reference topics

Consists of the guides presented by "git help --guides" command.

app/views/doc/_topics.html.erb

@@ -19,6 +19,7 @@
       <%= render 'shared/ref/admin' %>
       <%= render 'shared/ref/server' %>
       <%= render 'shared/ref/plumbing' %>
+      <%= render 'shared/ref/guides' %>
     </div>
   </div>
 </div>

app/views/doc/ref.html.erb

@@ -23,14 +23,15 @@
         <%= render 'shared/ref/sharing' %>
         <%= render 'shared/ref/inspection' %>
         <%= render 'shared/ref/patching' %>
+        <%= render 'shared/ref/debugging' %>
       </div>
       <div class='column-right'>
-        <%= render 'shared/ref/debugging' %>
         <%= render 'shared/ref/email' %>
         <%= render 'shared/ref/external' %>
         <%= render 'shared/ref/admin' %>
         <%= render 'shared/ref/server' %>
         <%= render 'shared/ref/plumbing' %>
+        <%= render 'shared/ref/guides' %>
       </div>
     </div>
   </div>

app/views/shared/ref/_guides.html.erb

@@ -0,0 +1,11 @@
+<h3 class='guides'>Guides</h3>
+<ul class='unstyled'>
+  <li><%= man('git-attributes') %></li>
+  <li><%= man('git-everyday') %></li>
+  <li><%= man('git-glossary') %></li>
+  <li><%= man('git-ignore') %></li>
+  <li><%= man('git-modules') %></li>
+  <li><%= man('git-revisions') %></li>
+  <li><%= man('git-tutorial') %></li>
+  <li><%= man('git-workflows') %></li>
+</ul>

config/initializers/categories.rb

@@ -27,6 +27,9 @@ module Gitscm
       ['git-cat-file', 'git-commit-tree', 'git-count-objects', 'git-diff-index',
        'git-diff-tree', 'git-hash-object', 'git-merge-base', 'git-read-tree',
        'git-rev-list', '']
+    ],['Guides',
+      ['git-attributes', 'git-everyday', 'git-glossary', 'git-ignore',
+       'git-modules', 'git-revisions', 'git-tutorial', 'git-workflows']
     ]
   ]
 end