Only swap the background color of the td if we know for sure that we are going

to be displaying one. Fixes the problem of blocks of tds that are all the same
color.

tools/generate-plugin-documentation.py

@@ -79,7 +79,6 @@ def makePluginDocumentation(filename):
         Detailed Help</td></tr>
         """) % (pluginName, cgi.escape(module.__doc__ or "")))
         for attr in dir(plugin):
-            trClass = trClasses[trClass]
             if plugin.isCommand(attr):
                 method = getattr(plugin, attr)
                 if hasattr(method, '__doc__'):
@@ -92,6 +91,7 @@ def makePluginDocumentation(filename):
                         morehelp = ' '.join(doclines)
                     help = cgi.escape(help)
                     morehelp = cgi.escape(morehelp)
+                    trClass = trClasses[trClass]
                     fd.write(textwrap.dedent("""
                     <tr class="%s"><td>%s</td><td>%s</td><td class="detail">%s
                     </td></tr>