Modernize email verification page
Summary: Fixes T3517. Moves the email verification page out of People and into Auth. Makes it look less awful.
Test Plan: {F49636} {F49637}
Reviewers: chad, btrahan
Reviewed By: btrahan
CC: aran
Maniphest Tasks: T3517
Differential Revision: https://secure.phabricator.com/D6425