[exim] Large Exim installs

I've been asked about large sites using Exim.

If you run what you consider to be a "large" install (at least a million
emails per day) could you please drop me a short note? With figures and
whether or not you're willing to be cited?

Hey, we can probably also put some advocacy info on the website, so let
me know if you're happy to be cited on www.exim.org. :)

Thanks,
-Phil