[TEAM] Image Testing - encryption

[flocculant at gmx.co.uk]

Currently when we test images we do so for:

- a simple boot of the image (which is new) just to prove the image gets 
as far as the desktop, if we actually get the jenkins for flavours up 
I'll be able to disable that.

- live session
- various partition variables for install
- post install test

Given this is an LTS I'm wondering if we should add Encrypt to the mix, 
just so we can at least be a bit more confident that nothing we do 
breaks it. Though I would, if we all think we should, prefer to make it 
optional rather than mandatory - don't want to make my day on 'release 
days' and harder :)

If nothing else we can be fairly certain that our users (or at least one 
or two) install like this - I've seen instances of /boot filling in #xubuntu

Thoughts will be handy :)

Cheers