Fix HTTPS issues for external images

[cuducos]

As we use image from third-party services, @qgustavor noted in #18 some of these services are not HTTPS strict. We need to find a way to serve all images safely.

Some ideas @turicas and I ventilated:

• Automate image generation from source using Imgur
• Spin up a thumbor instance

[Utkarsh-vishnoi]

Maybe a proxy would help in your case... The caveat in manually uploading the images to your server is that if the third-party services changes there images or logos, you have to upload the new image again. But proxy will securely fetch the data from your back-end, which will get the data from the third party server. The only caveat here is that the authentication between your server and the third party server is HTTP, but your app users will always get the image over HTTPS. Regards, Utkarsh Vishnoi