R1:eb6f4c4a28ca

Update PhortuneLanding page UI

Summary: Minor, uses 'user-circle' for account, and merchant logo for merchants in lists.

Test Plan: View the landing page, see updated logos and icons.

Reviewers: epriestley

Reviewed By: epriestley

Subscribers: Korvin

Differential Revision: https://secure.phabricator.com/D17586