Improved Redmine links:

* issue and changeset links generated only if the object exists
* issue subject and status appear in the link title
* strike issue link if issue is closed
* red wiki page link if page doesn't exist
* new icon for external links

Wiki page cache had to be disabled.

git-svn-id: http://redmine.rubyforge.org/svn/trunk@714 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/views/wiki/_content.rhtml

@@ -1,5 +1,3 @@
 <div class="wiki">
-  <% cache "wiki/show/#{content.page.id}/#{content.version}" do %>
-    <%= textilizable content.text, :attachments => content.page.attachments %>
-  <% end %>
+  <%= textilizable content.text, :attachments => content.page.attachments %>
 </div>