Update index.html with Discord link

Author: wyattrlindsey

index.html

@@ -60,6 +60,12 @@ <h3 class="text-center">
         <span class="button-icon" uk-icon="icon: github"></span>
         <span>Join Our GitHub</span>
     </a>
+	<a class="uk-button uk-button-primary uk-flex uk-flex-center"
+        href="https://discord.gg/yEbyed8e"
+        target="blank" rel="noopener">
+        <span class="button-icon" uk-icon="icon: discord"></span>
+        <span>Join Our Discord</span>
+    </a>
 </div>
 
 <div class="uk-child-width-expand@s uk-grid-match" uk-grid>