Add social links to footer

Adds social links for Facebook, Twitter, Instagram, Youtube, and an
external community (all defined in config.toml) to the footer.
Uses FontAwesome for the icon font.
Signed-off-by: Ethan Madison <ethan@ethanmad.com>

layouts/partials/footer.html

@@ -4,6 +4,7 @@
 </div> <!-- /.container -->
 
 <footer class="doc-footer">
+	{{ partial "social-links.html" . }}
 	{{ with .Site.Copyright | safeHTML }}<p>{{ . }}</p>{{ end }}
 </footer>
 

layouts/partials/social-links.html

+{{ with .Site.Params.social.facebook }}
+<a href="https://facebook.com/{{ . }}">
+    <i class="fa fa-facebook" alt="@{{ . }} on Facebook" title="See us at @{{ . }} on Facebook" aria-hidden="true"></i>
+</a>
+{{ end }}
+{{ if (isset .Site.Params.social "facebook") and (isset (.Site.Params.social "twitter" or .Site.Params.social "instagram" or .Site.Params.social "youtube" or .Site.Params.social "community")) }}
+&nbsp;
+{{ end }}
+{{ with .Site.Params.social.twitter }}
+<a href="https://twitter.com/{{ . }}">
+    <i class="fa fa-twitter" alt="Follow @{{ . }} on Twitter" title="Follow @um_fencing on Twitter" aria-hidden="true"></i>
+</a>
+{{ end }}
+{{ if (isset .Site.Params.social "twitter") and (isset (.Site.Params.social "instagram" or .Site.Params.social "youtube" or .Site.Params.social "community")) }}
+&nbsp;
+{{ end }}
+{{ with .Site.Params.social.instagram }}
+<a href="https://instagram.com/{{ . }}">
+    <i class="fa fa-instagram" alt="See our latest pictures on Instagram at @{{ . }}" title="See our latest pictures on Instagram at @{{ . }}" aria-hidden="true"></i>
+</a>
+{{ end }}
+{{ if (isset .Site.Params.social "instagram") and (isset (.Site.Params.social "youtube" or .Site.Params.social "community")) }}
+&nbsp;
+{{ end }}
+{{ with .Site.Params.social.youtube }}
+<a href="https://youtube.com/channel/{{ . }}">
+    <i class="fa fa-youtube" alt="Watch bouts and more on YouTube" title="Watch bouts and more on YouTube" aria-hidden="true"></i>
+</a>
+{{ end }}
+{{ if (isset .Site.Params.social "youtube") and (isset (.Site.Params.social "community")) }}
+&nbsp;
+{{ end }}
+{{ with .Site.Params.social.community }}
+<a href="{{ . }}">
+    <i class="fa fa-users" alt="Connect with us on our community page" title="Connect with us on our community page" aria-hidden="true"></i>
+</a>
+{{ end }}