Improve footer link flexibility

Deprecate hardcoded footer links in favor or new `footer.links` array for any link and in any order. All of Font Awesome's icons are available for use.

```
footer:
  links:
    - label: "Twitter"
      icon: "fab fa-fw fa-twitter-square"
      url: "https://twitter.com/username"
    - label: "GitHub"
      icon: "fab fa-fw fa-github"
      url: "https://github.com/username"
    - label: "Instagram"
      icon: "fab fa-fw fa-instagram"
      url: "https://instagram.com/username"
```

_config.yml

@@ -125,6 +125,28 @@ author:
       icon: "fab fa-fw fa-instagram"
       # url: "https://instagram.com/"
 
+# Site Footer
+footer:
+  links:
+    - label: "Twitter"
+      icon: "fab fa-fw fa-twitter-square"
+      # url:
+    - label: "Facebook"
+      icon: "fab fa-fw fa-facebook-square"
+      # url:
+    - label: "GitHub"
+      icon: "fab fa-fw fa-github"
+      # url:
+    - label: "GitLab"
+      icon: "fab fa-fw fa-gitlab"
+      # url:
+    - label: "Bitbucket"
+      icon: "fab fa-fw fa-bitbucket"
+      # url:
+    - label: "Instagram"
+      icon: "fab fa-fw fa-instagram"
+      # url:
+
 
 # Reading Files
 include:

_includes/footer.html

@@ -3,21 +3,15 @@
     {% if site.data.ui-text[site.locale].follow_label %}
       <li><strong>{{ site.data.ui-text[site.locale].follow_label }}</strong></li>
     {% endif %}
-    {% if site.twitter.username %}
-      <li><a href="https://twitter.com/{{ site.twitter.username }}"><i class="fab fa-fw fa-twitter-square" aria-hidden="true"></i> Twitter</a></li>
+
+    {% if site.footer.links %}
+      {% for link in site.footer.links %}
+        {% if link.label and link.url %}
+          <li><a href="{{ link.url }}"><i class="{{ link.icon | default: 'fas fa-link' }}" aria-hidden="true"></i> {{ link.label }}</a></li>
         {% endif %}
-    {% if site.facebook.username %}
-      <li><a href="https://www.facebook.com/{{ site.facebook.username }}"><i class="fab fa-fw fa-facebook-square" aria-hidden="true"></i> Facebook</a></li>
-    {% endif %}
-    {% if site.author.github %}
-      <li><a href="https://github.com/{{ site.author.github }}"><i class="fab fa-fw fa-github" aria-hidden="true"></i> GitHub</a></li>
-    {% endif %}
-    {% if site.author.gitlab %}
-      <li><a href="https://gitlab.com/{{ site.author.gitlab }}"><i class="fab fa-fw fa-gitlab" aria-hidden="true"></i> Gitlab</a></li>
-    {% endif %}
-    {% if site.author.bitbucket %}
-      <li><a href="https://bitbucket.org/{{ site.author.bitbucket }}"><i class="fab fa-fw fa-bitbucket" aria-hidden="true"></i> Bitbucket</a></li>
+      {% endfor %}
     {% endif %}
+
     <li><a href="{% if site.atom_feed.path %}{{ site.atom_feed.path }}{% else %}{{ '/feed.xml' | relative_url }}{% endif %}"><i class="fas fa-fw fa-rss-square" aria-hidden="true"></i> {{ site.data.ui-text[site.locale].feed_label | default: "Feed" }}</a></li>
   </ul>
 </div>

docs/_config.yml

@@ -118,6 +118,20 @@ author:
       url: "https://instagram.com/mmistakes"
 
 
+# Site Footer
+footer:
+  links:
+    - label: "Twitter"
+      icon: "fab fa-fw fa-twitter-square"
+      url: "https://twitter.com/mmistakes"
+    - label: "GitHub"
+      icon: "fab fa-fw fa-github"
+      url: "https://github.com/mmistakes"
+    - label: "Instagram"
+      icon: "fab fa-fw fa-instagram"
+      url: "https://instagram.com/mmistakes"
+
+
 # Reading Files
 include:
   - .htaccess

docs/_docs/05-configuration.md

@@ -768,6 +768,35 @@ author:
 
 To customize the author sidebar, read the full [layout documentation]({{ "/docs/layouts/#author-profile" | relative_url }}).
 
+## Site Footer
+
+Footer links can be added under the `footer.links` array.
+
+| Name | Description |
+| --- | --- |
+| **label** | Link label (e.g. `"Twitter"`) |
+| **icon** | [Font Awesome icon](https://fontawesome.com/icons?d=gallery) classes (e.g. `"fab fa-fw fa-twitter-square"`) |
+| **url** | Link URL (e.g. `"https://twitter.com/mmistakes"`) |
+
+```yaml
+footer:
+  links:
+    - label: "Twitter"
+      icon: "fab fa-fw fa-twitter-square"
+      url: "https://twitter.com/mmistakes"
+    - label: "GitHub"
+      icon: "fab fa-fw fa-github"
+      url: "https://github.com/mmistakes"
+    - label: "Instagram"
+      icon: "fab fa-fw fa-instagram"
+      url: "https://instagram.com/mmistakes"
+```
+
+**Note:** Twitter and Facebook footer links no longer automatically pull from `site.twitter.username` and `site.facebook.username`. This behavior has been deprecated in favor of the `footer.links` array above.
+{: .notice--danger}
+
+To change "Follow:" text that precedes footer links, edit the `follow_label` key in `_data/ui-text.yml`.
+
 ## Reading Files
 
 Nothing out of the ordinary here. `include` and `exclude` may be the only things you need to alter.

test/_config.yml

@@ -106,6 +106,20 @@ author:
       url: "https://instagram.com/"
 
 
+# Site Footer
+footer:
+  links:
+    - label: "Twitter"
+      icon: "fab fa-fw fa-twitter-square"
+      url: "https://twitter.com/"
+    - label: "GitHub"
+      icon: "fab fa-fw fa-github"
+      url: "https://github.com/"
+    - label: "Instagram"
+      icon: "fab fa-fw fa-instagram"
+      url: "https://instagram.com/"
+
+
 # Reading Files
 include:
   - .htaccess