Extract partial
Update regression specs - extra space shouldn't matter in HTML
Move the box into the partial too
Randomly show a different promo in email alerts

Add a dummy promo for OpenAustralia.org and randomly show it instead
of the Right To Know promo
Replace custom matcher with built in Capybara one
Exclude the randomised promo from email regression tests
Extract method
Don't test rendering the promo because it's random

I toyed with the idea of testing if the rendered email contained
either promo but that would mean you've got a random element in your
tests, i.e. it may fail or succeed depending on which random partial
gets chosen.

I'd still like a way to test the render_random_promo method.
Replace rotating promo with a far simpler one for all our projects

I started this by wanting to cut down the size of the promo as it's
too loud right now. Maybe OK for our new project but for everyday
alerts it's not nice for the user to have this Big Honking Promo on
every email.

Anyway, I started cutting down the size and realised I could simplify
this right down to a promo for all the projects in one sentence. I
liked it and also like the fact it cuts down the complexity of the
implementation. Let's see how it performs and go from there.
Merge email promo topic branch