Resolve ambiguity in photo copyright terms, improper use, and inconsistent permissions

[pmk01]

The copyright options on the photo upload page are unsatisfactory. We need options which cover all scenarios, (including occasions when a candidate wants a photo removed after the election?).

Suggestions by JF & ML in this doc.

[semiprime]

Additional option suggestion: I've seen people submit photos from Wikipedia/Wikimedia, which tend to be CC-BY (i.e. attribution) licenses. It would be good to be able to accept these. However, there's no way that I see to provide an attribution, and any attribution would need to be available somewhere on WCIVF & candidates websites.