PEP8 style fixes and other small style fixes

I used autopep8 on some files and did carefully check the changes.
I ignored E501,E302,E231,E225,E222,E221,E241,E203 in my search, and at
least E501 on any autopep8 run.

Other style fixes not related to PEP8:
* Only use new-style classes. I don't think the usage of old-style
  classes was voluntary. Old-style classes are removed in Python 3.
* Convert an if/else to a one-liner in mediawiki, change docstring style
  change to a comment something that wasn't really appropriate for a
  docstring.
* Unneeded first if condition in meteofrance

modules/fourchan/backend.py

@@ -68,7 +68,7 @@ class FourChanBackend(BaseBackend, ICapMessages):
             thread = Thread(id)
         thread.title = _thread.filename
         thread.root = Message(thread=thread,
-                              id=0, # root message
+                              id=0,  # root message
                               title=_thread.filename,
                               sender=_thread.author,
                               receivers=None,