createfolders setting is ignored if readonly is True (6.5.4)

[Vladimir Nesov]

Seem like there was a bug in the new get_create_folders method: 
if 'readonly' flag is set to true, folders are created 
regardless of 'createfolders'. The following change 
(over 6.5.4 tag) fixed the problem for me:

--- a/offlineimap/repository/Base.py
+++ b/offlineimap/repository/Base.py
@@ -134,7 +134,7 @@ class BaseRepository(CustomConfig.ConfigHelperMixin, object)
 
         It is disabled by either setting the whole repository
         'readonly' or by using the 'createfolders' setting."""  
-        return self._readonly or self.getconfboolean('createfolders', True)
+        return (not self._readonly) and self.getconfboolean('createfolders', Tr
 
     def makefolder(self, foldername):
         """Create a new folder"""