Easy spacing fixes, trailing stuff

Remove useless trailing \
Remove trailing spaces
Add missing empty lines

autopep8 -ir -j2 --select=E301,E302,E502,W291,W293,W391 .

Diff quickly checked.

weboob/capabilities/chat.py

@@ -51,6 +51,7 @@ class ChatMessage(CapBaseObject):
         if self.date is None:
             self.date = datetime.datetime.utcnow()
 
+
 class ICapChat(IBaseCap):
     """
     Websites with a chat system.