Candidate email and related issues

[pmk01]

When a profile has an email but not much else attached, we offer an 'email the candidate' feature.

Do we know if this is ever used? If not, I think we should remove it. (I think this action would close this: #121)

When a profile doesn't have an email attached, we offer the text: "We don't know [candidate]'s email address. Can you add it?"

This is often the largest and most prominent thing in the 'online' section of the profile. I think we should remove it as we already provide a CTA link to edit the profile at the bottom of the page.

Relatedly: DemocracyClub/yournextrepresentative#1621

[VirginiaDooley]

From @pmk01
We want to replace the email card

with "Are you this candidate? Find out how you can update your profile

[pmk01]

#1634