[Design] Cosmo signup: tell users why email required

[Jared Rhine]

Proposal: update the Cosmo signup form to say "we'll send a link to the 
provided email address for you to finalize your signup".

A scan of Chandler Hub signups shows about 10-15% of failed signup 
activations are using an obviously-bogus email address.

Currently, all fields in the signup form are marked as "required".  But 
seriously, have you ever lied on a signup form when a field is marked 
required?  Some sites say "required" for marketing purposes, even if 
they aren't going to validate the submitted email.  But we are.

So I propose a modification, to be included in Cosmo 0.7 (or 0.6.1), 
where if Cosmo is configured to require email activation, the signup 
form says not only that all fields are required, but that the email 
address will be validated before an account is granted.

Right now, they get a followup screen, after signup, telling them a 
validation email will be sent to the provided email address.  But by 
that point, it's too late for them to fix their email if they fibbed 
initially.

The intent is to keep people from wasting their time trying to sign up 
for an account with a bogus email.  Not only will they not get their 
account, but by virtue of trying, they've locked out that username from 
future attempts by themselves or others.

BTW, we're running about 1-4 failed activations a day on osaf.us (of 
which about 10-15% are bogus emails, but the rest are not.)  We've no 
way currently to determine why these account signups are not getting 
activated.

-- Jared