Issue #185 - email signups now sent to the correct address

I added the staff_email address to the secrets file. Now, in every env except prod, the email will be sent to the dummy email address.
You would think that the existence of this section means that it's actually used, but on staging we run with a production configuration.  So this still won't work.  One option is to change that and run with the rails staging config on the staging server.  The reason not to do that is that we want staging to mirror production almost exactly so there are no surprises.  However, maybe that's not a valid reason.  The other option seems to be to tie it to an ENV variable instead and then I'll have to go set that ENV variable properly in production and staging.  Any thoughts here?