Title: Improved handling of wrong encoded input strings
Level: 1
Component: multisite
Compatible: compat
Version: 1.2.8b1
Date: 1450428996
Class: fix

When a user submitted non UTF-8 encoded strings, for example latin-1 encoded ones,
where we expect to get a UTF-8 encoded string, this resulted in a cryptic exception.
This has been fixed now by raising an understandable error message in most places.
