Show Commons link to logged out users

Change-Id: I899cb36a5d25342325266b68a3fd8058f3129e78
Mingle: https://wikimedia.mingle.thoughtworks.com/projects/multimedia/cards/429
(cherry picked from commit 92e68e40139e21d0952b39230ae18c4ae928a590)
Merge "Show Commons link to logged out users" into wmf/1.24wmf8