Update index.html

Updating definition of inbox based on erratum. See #289 for discussion.

Author: evanp

index.html

@@ -735,8 +735,7 @@ <h2><i>Actor</i> objects</h2>
         <dl>
           <dt id="inbox-property">inbox</dt>
           <dd>
-            A reference to an [[!ActivityStreams]]
-            <a href="https://www.w3.org/TR/activitystreams-vocabulary/#dfn-orderedcollection">
+            An <a href="https://www.w3.org/TR/activitystreams-vocabulary/#dfn-orderedcollection">
               <code>OrderedCollection</code></a>
             comprised of all the messages received by the actor; see
             <a href="#inbox"></a>.