Add support for rel attribute in social media links (#92)

Particularly rel="me" is of interest when verifying links
in for instance a Mastodon profile.

Author: hlindqvist

_includes/header.html

@@ -4,9 +4,9 @@
     <span class="social_links">
         {% for link in site.dash.social_links %}
         {% if link.fa == true %}
-        <a class="color-{{ link.color }}-hover" href="{{ link.url }}"><i class="fa fa-{{ link.icon }}"></i></a>
+        <a class="color-{{ link.color }}-hover" href="{{ link.url }}"{% if link.rel %} rel="{{ link.rel }}"{% endif %}><i class="fa fa-{{ link.icon }}"></i></a>
         {% else %}
-        <a class="color-{{ link.color }}-hover" href="{{ link.url }}"><i class="fab fa-{{ link.icon }}"></i></a>
+        <a class="color-{{ link.color }}-hover" href="{{ link.url }}"{% if link.rel %} rel="{{ link.rel }}"{% endif %}><i class="fab fa-{{ link.icon }}"></i></a>
         {% endif %}
         {% endfor %}
     </span>