Create an endpoint which returns member logos

It would be helpful to have a URL which returns an organization logo that could simply be passed to an img's src attribute.

Similar to how it's done on accounts.eclipse.org:

https://accounts.eclipse.org/user/cguindon/picture

The URL could be something like:

https://membership.eclipse.org/api/organizations/656/logos/web

For context, this is being requested because of the following bug: eclipse.org#503 (closed). During the /membership/ migration efforts, we removed some scripts. One of these scripts was fetching logos. Instead of creating a new JS widget to fetch a single logo, it may be better to have access to logos as simple URLs.