Use newer form of catching exceptions

autopep8 -i --select=W602
Also some other minor deprecated syntax changes, like "while 1".
I did not commit the less obvious changes.

weboob/applications/boobmsg/boobmsg.py

@@ -373,7 +373,7 @@ class Boobmsg(ReplApplication):
 
             try:
                 self.do('post_message', message, backends=backend_name).wait()
-            except CallErrors, errors:
+            except CallErrors as errors:
                 self.bcall_errors_handler(errors)
             else:
                 if self.interactive: