Pull user dropdowns in navbar right

Summary:
Minor UI tweak in base template (M1)

Also arcconfig file to define phab upstream

Test Plan: Tested on webdns4.staging.grnet.gr

Reviewers: #webdns4, ctrochalakis

Reviewed By: #webdns4, ctrochalakis

Subscribers: #webdns4

Differential Revision: https://repo.grnet.gr/D5