UC-99 Manually confirm fb users who don't have email addresses with fb

When a user connects via Facebook but doesn't have an email registered with Facebook (eg, if they registered using a phone number), we have them enter an email address for us to use. We want to have user's confirm those email addresses. If they come from Facebook, then we'll still auto-confirm them.

Ticket: https://wikia-inc.atlassian.net/browse/UC-99
I borrowed this logic from [here](https://github.com/Wikia/app/blob/dev/extensions/wikia/UserLogin/js/UserLoginAjaxForm.js#L106-L114) without investigating why it's being sent as a POST. It looks like the answer is: no good reason at all. I'll update.