fixes

- parse video xml with lxml instead of regexpes
- add a prefix to IDs to know what kind of object it is

modules/arte/video.py

@@ -31,6 +31,9 @@ class ArteVideo(BaseVideo):
 
 
 class ArteLiveVideo(BaseVideo):
+    def __init__(self, _id, *args, **kwargs):
+        BaseVideo.__init__(self, 'live.%s' % _id, *args, **kwargs)
+
     @classmethod
     def id2url(cls, _id):
         return 'http://arte.vo.llnwd.net/o21/liveweb/events/event-%s.xml' % _id