Fallback further than gravitar when default

[devinmatte]

I generally dislike when users have no profile image. Because of that I would like to see if we could fall back further than just using gravitar with the csh email. I would like to see it fall back to use:

• Google account with gravitar if the user has added their Google account to profiles
• GitHub username profile image?
• See if we can grab RIT id photos

[liam-middlebrook]

Sometimes users add other emails, I think a good fallback would be to iterate over the listed addresses.

[evelyndooley]

So far we have Twitter and Github images, currently working on adding more