Full https
We should have this svg `http://slack.crocodilejs.com/badge.svg` served with __https__ before the final release. Right now browsers warn users about our website security just because of that image.

<img width="567" alt="captura de pantalla 2017-12-26 a las 17 22 12" src="https://user-images.githubusercontent.com/4324982/34360476-7ce799b8-ea61-11e7-9d46-321dd7a801e0.png">
