Update footer with CC-by-sa 4.0 license

Author: annegentle

_includes/footer.html

@@ -1,6 +1,6 @@
 {% if site.owner.google.ad-client and site.owner.google.ad-slot %}{% include ad-footer.html %}{% endif %}
 
-<span>&copy; {{ site.time | date: '%Y' }} {{ site.owner.name }}. Powered by <a href="http://jekyllrb.com" target="_blank" rel="nofollow">Jekyll</a> using the <a href="https://mademistakes.com/work/so-simple-jekyll-theme/" target="_blank" rel="nofollow">So Simple Theme</a>.</span>
+<span>&copy; {{ site.time | date: '%Y' }} {{ site.owner.name }}, Licensed <a href="https://creativecommons.org/licenses/by-sa/4.0/">CC-BY-SA 4.0</a>. </br> Powered by <a href="http://jekyllrb.com" target="_blank" rel="nofollow">Jekyll</a> using the <a href="https://mademistakes.com/work/so-simple-jekyll-theme/" target="_blank" rel="nofollow">So Simple Theme</a>. Hosted on <a href="https://pages.github.com">GitHub Pages</a>, source stored on <a href="https://github.com/justwriteclick/docslikecode">Github</a>.</span>
 <div class="social-icons">
 	{% if site.owner.twitter %}<a href="https://twitter.com/{{ site.owner.twitter }}" title="{{ site.owner.name}} on Twitter" target="_blank"><i class="fa fa-twitter-square fa-2x"></i></a>{% endif %}
 	{% if site.owner.facebook %}<a href="https://facebook.com/{{ site.owner.facebook }}" title="{{ site.owner.name}} on Facebook" target="_blank"><i class="fa fa-facebook-square fa-2x"></i></a>{% endif %}