Modularize into template files, add root gen

Removes most of the inline HTML to their own files
Uses the most basic setup to create links for all the existing index
files created with GenTemplate

templates/card.html

@@ -0,0 +1,8 @@
+<div class="col-md-3">
+  <a href="{{FULLLINK}}" target="{{FULLLINK}}">
+      <div class="card mb-3 bg-dark text-white">
+          <div class="card-header">{{TITLE}}</div>
+          <img class="card-img" width="250" src="{{THUMBNAIL}}" />
+      </div>
+  </a>
+</div>