Fix a regression in accessing the username for the session.

Review Request #6900 — Created Feb. 3, 2015 and submitted — Latest diff uploaded

Information

RBTools
release-0.7.x
fd3ce84...

Reviewers

My previous optimization to fetching the user resource along with the
session broke the get_username() function, which attempted to follow a
now non-existent link. It's been updated to get the expanded user
resource instead and access the username from that.

Ran rbt status. Before, it would crash with an attribute error. After,
it showed me a list of my open review requests.