Use a scoped, rather than an embedded context for default language example.

Fixes #250.

Author: gkellogg

index.html

@@ -4994,23 +4994,23 @@ <h3>Using the Document Base for the Default Vocabulary</h3>
     <a>string</a> values that are not <a href="#type-coercion">type coerced</a>.</p>
 
   <p>To clear the <a>default language</a> for a subtree, <code>@language</code> can
-    be set to <code>null</code> in a <a>local context</a> as follows:</p>
+    be set to <code>null</code> in an intervening context, such as a <a>scoped context</a> as follows:</p>
 
   <pre class="example nohighlight" data-transform="updateExample"
        title="Clearing default language">
   <!--
   {
     "@context": {
       ####...####
-      "@language": "ja"
+      "@language": "ja",
+      "details": {
+        ****"@context": {
+          "@language": null
+        }****
+      }
     },
     "name": "花澄",
-    "details": {
-      ****"@context": {
-        "@language": null
-      }****,
-      "occupation": "Ninja"
-    }
+    "details": {"occupation": "Ninja"}
   }
   -->
   </pre>