R1:5f3753e2317d

Clean up spacing, sizing on mobile app menus

Summary: Lots of minor spacing/alignment tweaks on mobile menus

Test Plan: set browser to 320 width, inspect for issues and alignments

Reviewers: btrahan, epriestley

Reviewed By: epriestley

Subscribers: Korvin, epriestley

Differential Revision: https://secure.phabricator.com/D10937