People page image lazy loading

[silva-nick]

We want to find some way to speed up the loading of images for the people page.

Expected:

Faster loading of images via some sort of lazy loading:

1. Load lower res images first then query for higher resolution (I think we already have something like this)
2. Don't load DAML Alumni until the rest of DAML has loaded

Actual:

Loading images for everyone in DAML takes a really long time now (4-5 seconds).