chore(docs): adds types column and null checks for description (#7713)

* chore(docs): adds types column and null checks for description

* chore(nit): update per pr feedback

tools/dgeni/templates/method.template.html

@@ -9,11 +9,13 @@
       </th>
     </tr>
   </thead>
+  {%- if method.description -%}
   <tr class="docs-api-method-description-row">
     <td colspan="2" class="docs-api-method-description-cell">
       {$ method.description | marked | safe $}
     </td>
   </tr>
+  {%- endif -%}
 
   {%- if method.params.length -%}
   <thead>

tools/dgeni/templates/property.template.html

@@ -25,7 +25,11 @@
     <p class="docs-api-property-name">
       {$ property.name $}
     </p>
-    <code class="docs-api-property-type">{$ property.type $}</code>
   </td>
-  <td class="docs-api-property-description">{$ property.description | marked | safe $}</td>
+  <td class="docs-api-property-description">
+    <div class="docs-api-property-type">
+      Type: <code>{$ property.type $}</code>
+    </div>
+    {$ property.description | marked | safe $}
+  </td>
 </tr>