Move method source block to the top

Currently, if a method description is long (e.g. `Array.new`), users need
to click the method toggle button next to the method title, and then scroll
down to the source code expanded below the description.

This commit changes the behavior so that the source code is expanded
immediately below the method title.

Author: st0012

lib/rdoc/generator/template/darkfish/class.rhtml

@@ -130,6 +130,11 @@
 
         <%- unless method.skip_description? then -%>
         <div class="method-description">
+          <%- if method.token_stream then -%>
+          <div class="method-source-code" id="<%= method.html_name %>-source">
+            <pre><%= method.markup_code %></pre>
+          </div>
+          <%- end -%>
           <%- if method.comment then -%>
           <%= method.description.strip %>
           <%- else -%>
@@ -144,12 +149,6 @@
               %>
             </div>
           <%- end -%>
-
-          <%- if method.token_stream then -%>
-          <div class="method-source-code" id="<%= method.html_name %>-source">
-            <pre><%= method.markup_code %></pre>
-          </div>
-          <%- end -%>
         </div>
         <%- end -%>