Add option to display primary email on public profile

[di]

What's the problem this feature will solve?
Currently there's no way to publicly display an email address as a point of contact for a PyPI account. Instead, maintainer/author emails for a user's packages must be used instead.

Describe the solution you'd like
Similar to Github, on the "Account Settings" page, we should have an option such as:

☑️Keep my email address private
We won't show your primary email on your public PyPI profile page.

This should default to "True" for all new and existing users.

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[pradyunsg]

This would be a great addition! :D

[brainwane]

@pgadige is this something you'd like to try working on?

[pgadige]

Thank you, @brainwane, for suggesting this one. I'm working on it.

[brainwane]

@pgadige How is it going? Do you have a branch somewhere that we can look at?

[pgadige]

@brainwane, I'm figuring out few JavaScript things (I'm a newbie to JS) for displaying the email address properly on the page. I managed to break the CSS of the page couple of times. I think I'll try to submit a PR by the EOD so the reviewers can show me what exactly I'm doing wrong.

[brainwane]

@pgadige Looking forward to that PR!

[brainwane]

I just emailed with @pgadige and she'll be working on sharing a work-in-progress pull request with us in the next few days.

@pgadige: If you are working on this issue and have questions or get stuck, please feel free to speak up here, or in #pypa-dev on Freenode, or on the pypa-dev mailing list.