Issues when loading Flickr URLs using HTTPS

[cfviotti]

If we paste Flickr URLs with HTTPS in the "Multimedia URL" field and click "Load", it will fail to to actually do it. The foreground log then outputs:

collective.oembed says: "There are no endpoints available for [pasted URL using https]"

Note that Flickr is accessed by default using HTTPS, so when we copy/paste the URL from a browser's address bar, it will include it in the beggining.

[hvelarde]

seems to be related with #13 also.