localeval: comment on security issues

Minor syntax fixes.

Signed-off-by: Nicolas Sebrecht <nicolas.s-dev@laposte.net>

offlineimap/localeval.py

@@ -1,7 +1,6 @@
 """Eval python code with global namespace of a python source file."""
 
-# Copyright (C) 2002 John Goerzen
-# <jgoerzen@complete.org>
+# Copyright (C) 2002-2014 John Goerzen & contributors
 #
 #    This program is free software; you can redistribute it and/or modify
 #    it under the terms of the GNU General Public License as published by
@@ -24,10 +23,16 @@ except:
     pass
 
 class LocalEval:
+    """Here is a powerfull but very dangerous option, of course.
+
+    Assume source file to be ASCII encoded."""
+
     def __init__(self, path=None):
         self.namespace = {}
 
         if path is not None:
+            # FIXME: limit opening files owned by current user with rights set
+            # to fixed mode 644.
             file = open(path, 'r')
             module = imp.load_module(
                 '<none>',