Give rendered-data sections a background and some padding (#1195)

Gives definition sections for APIs, events, etc a background and a small indent, which I find very helpful to guide the eye.

layouts/partials/openapi/render-object-table.html

@@ -21,7 +21,7 @@
 
 {{ if $properties }}
 
-<table{{ if .anchor }} id="{{ .anchor }}"{{ end }}>
+<table{{ if .anchor }} id="{{ .anchor }}"{{ end }} class="object-table">
  {{ with $title }}
  <caption>{{ . }}</caption>
  {{ end }}

layouts/partials/openapi/render-responses.html

@@ -20,7 +20,7 @@
 
 <h2>Responses</h2>
 
-<table class>
+<table class="response-table">
  <thead>
   <th class="col-status">Status</th>
   <th class="col-status-description">Description</th>