Load Gravatar over HTTPS

To avoid Google Chrome (and other browsers) display insecure resources warning:

> However, this page includes other resources which are not secure. These resources can be viewed by others while in transit, and can be modified by an attacker to change the look of the page.
Merge pull request #67 from dentarg/patch-1

Load Gravatar over HTTPS
Fixing gravatar tests.
Update Gruntfile.js
Release: 6.3.3
Update pt-BR dictionary
Release: 6.3.4
Update deploy script for #70 with @jfromaniello suggestion
Release: 6.3.5
Update deploy script for #70
Fix deploy script oddly not adding build/ after updating .gitignore
Fix README.md
Trying position absolute instead of static for overlay
Release: 6.3.6
Update README.md
Update README.md
Update README.md
Add changelog file History.md. Fix #72
Update font for icons
Release: 6.3.7