imgur content might not provide 'as'

[saiichihashimoto]

Also, this opens up an xss injection.

https://sentry.io/kogg/hovercards/issues/156165011/

TypeError: model[_.result(...)] is not a function
  File "/app/integrations/imgur/index.js", line 20, in Object.api.content
    return model[_.result(args, 'as')](_.pick(args, 'id'), null, usage)
  File "/app/server/v2.js", line 46, in null.<anonymous>
    integrations[req.params.integration].content(Object.assign({}, req.headers, req.query, { id: req.params.id }))
  File "/app/server/v2.js", line 39, in null.<anonymous>
    next();
...
(54 additional frame(s) were not displayed)

TypeError: model[_.result(...)] is not a function