Fixed name resolution in OAuth token

Some users don't actually have a fullName in launchpad. Others only have
a single word. Some have many words. This adds a bit of handling to make
those names behave nicely, though ultimately I think we should get rid of
first_name and last_name and just use full_name.

Change-Id: I64dceaaa87781f928b3a4fbf3a15de4f74f994e0