Move visualize button outside of controls block

visualizer/templates/plotter.html

@@ -71,9 +71,10 @@
       </li>
       {% endfor %}
     </ul>
-    <input id="visualize" type="submit" value="Visualize">
   </form>
 
+  <input id="visualize" form="controls" type="submit" value="Visualize">
+
   <div id="visualization">
     <div id="plot">
     {% if g.selection_complete %}