R1:117589c160f6

Clean up Login, Responsive Forms

Summary: Removes the panel-view on login and adds additonal responsive styles for mobile forms.

Test Plan: View in mobile browser, resize page.

Reviewers: epriestley, btrahan

Reviewed By: epriestley

CC: aran, Korvin

Differential Revision: https://secure.phabricator.com/D4530