Switch to side-by-side view

--- a/src/filters/rclopxml.py
+++ b/src/filters/rclopxml.py
@@ -146,7 +146,7 @@
         return stylesheet
     
     def extractone(self, params):
-        if not params.has_key("filename:"):
+        if "filename:" not in params:
             self.em.rclog("extractone: no mime or file name")
             return (False, "", "", rclexecm.RclExecM.eofnow)
         fn = params["filename:"]