Link user name in People log view to user page

Summary:
Looking at IPs who recently registered more than one account in
Phabricator and trying to figure out whether they are spam bots
or just all on the same university network, I often want to check
recent user activity of these accounts. Hence linking the entries
in the User column to their user page comes in handy.

Test Plan: Tested on local instance and works as expected.

Reviewers: #blessed_reviewers, epriestley

Reviewed By: #blessed_reviewers, epriestley

Subscribers: epriestley

Differential Revision: https://secure.phabricator.com/D16620