Automatically scroll down to the preview when previewing wiki page.

git-svn-id: http://redmine.rubyforge.org/svn/trunk@712 e93f8b46-1217-0410-a6f0-8f06a7374b81

app/views/wiki/edit.rhtml

                        { :url => { :controller => 'wiki', :action => 'preview', :id => @project, :page => @page.title },
                          :method => 'post',
                          :update => 'preview',
-                         :with => "Form.serialize('wiki_form')"
+                         :with => "Form.serialize('wiki_form')",
+                         :complete => "location.href='#preview-top'"
                        } %></p>
 <%= wikitoolbar_for 'content_text' %>
 <% end %>
 
+<a name="preview-top"></a>
 <div id="preview" class="wiki"></div>
 
 <% content_for :header_tags do %>