Display images submitted via API

[tmtmtmtm]

Currently images are only displayed if they're submitted via the UI (#214) — image URLs submitted via the API are completely ignored (i.e. they don't even appear as a URL in the UI, never mind being displayed).

e.g. compare http://eduskunta.popit.mysociety.org/persons/popit.eduskunta/person/109 with http://eduskunta.popit.mysociety.org/api/v0.1/persons/popit.eduskunta/person/109

[tfgg]

I'm also getting this for my upload of yournextmep data. Not vastly important, but would be nice to be able to link to my own CDN.

[jacksonj04]

👍 for use at http://leedscitycouncil.popit.mysociety.org

[chrismytton]

Fixed in mysociety/popit-api@e95568b