So Devise actually already has an email regex and performs validations, but we've been calling `#create` and swallowing the error for a while. In addition to that, the e-mail regex is not perfect as others have reported that they can sign up successfully with a bad e-mail address.

Unfortunately, the only way to reliably remove Devise's e-mail format regex was to remove the `validatable` module. The current recommendation is to just copy over the validations we need, which is why I threw in these lines - https://github.com/codetriage/codetriage/pull/115/files#L2R7-8