Expandable profile pictures

[JoelEager]

(This suggestion was raised in the packet post mortem on 9/25.)

The profile pictures shown in packet are a bit too small to be useful in helping recognize people. It'd be nice if there was an option to enlarge them. Maybe you'd tap on the image to see a larger view in a dialog? This should support both mobile and desktop users and it needs to apply to both upperclassmen and freshman use cases.