can't remove headshot once it's been added

[davewhiteland]

If a speaker has a headshot, I can't remove it in Edit speaker by just deleting the URL: empty input is accepted, URL does not appear there in subsequent edits, but the image persists.

My babyish attempts to force new content have lead me to believe this isn't simply an image caching problem, but I haven't tried on a local install yet.