display student username if name not present on templates
there are a number of places that say 'Hello, Greg!' directly to the user, or otherwise refer to student's names, such as on the room and floor pages, the search page, the major pages, and the profile page
except that if for some reason you don't have a name set (wasn't on peoplefinder, you deleted it, only set a last name... who knows, users be crazy)
it just says 'Hello, !', or is '' empty
helpful hint: empty values evaluate to False
usernames will always be present, so default to a user's username if their name isn't set ('Hello, dbond2!')