Fix config reference

Author: lrdodge

_includes/nav.html

@@ -60,7 +60,7 @@ <h4>{{ site.title }}</h4>
                         <a href="https://youtube.com/user/{{ site.youtube }}" target="_blank" rel="noopener noreferrer"><i class="fa fa-fw fa-youtube-square"></i> Youtube</a>
                     </li>{% endif %}
                     {% if site.youtube-channel %}<li>
-                        <a href="https://youtube.com/channel/{{ site.youtube }}" target="_blank" rel="noopener noreferrer"><i class="fa fa-fw fa-youtube"></i> Youtube</a>
+                        <a href="https://youtube.com/channel/{{ site.youtube-channel }}" target="_blank" rel="noopener noreferrer"><i class="fa fa-fw fa-youtube"></i> Youtube</a>
                     </li>{% endif %}
                     {% if site.soundcloud %}<li>
                         <a href="http://soundcloud.com/{{ site.soundcloud }}" target="_blank" rel="noopener noreferrer"><i class="fa fa-fw fa-soundcloud"></i> SoundCloud</a>