convertFile: hack to force the use of wkhtmltopdf in some case

Force the use of wkhtmltopdf if:
- source format is html
- destination format is pdf
- conversion_kw is not empty

cloudooo/manager.py

@@ -119,7 +119,13 @@ class Manager(object):
     try:
       self.kw['zip'] = zip
       self.kw['refresh'] = refresh
-      handler_class = getHandlerClass(source_format,
+      if (conversion_kw and
+          source_format in ("html", "text/html") and
+          destination_format in ("pdf", "application/pdf")):
+        from cloudooo.handler.wkhtmltopdf.handler import Handler as WkhtmltopdfHandler
+        handler_class = WkhtmltopdfHandler
+      else:
+        handler_class = getHandlerClass(source_format,
                                     destination_format,
                                     self.mimetype_registry,
                                     self.handler_dict)