A short todo for messageviewer items are sorted in no particular order...

* Write unittests especially for the crypto stuff (look at messagecomposer for setup, lfranchi might know more).
* Add a "message decryption complete" signal (or similar) for frontends to use when saving a decrypted message is required by law...
* Split the display widget into two, one for headers and status (read crypto) information and one for the message body. This to eliminate the possibility of faking a message.
