Add a <p><ul> to "Properties of the Iterator Constructor"

All other "Properties of the Foo Constructor" sections
start with a <p><ul> where, at the very least,
you say what the constructor's [[Prototype]] is.

Author: jmdyck

spec.html

@@ -46589,6 +46589,11 @@ <h1>Iterator ( )</h1>
 
       <emu-clause id="sec-properties-of-the-iterator-constructor">
         <h1>Properties of the Iterator Constructor</h1>
+        <p>The Iterator constructor:</p>
+        <ul>
+          <li>has a [[Prototype]] internal slot whose value is %Function.prototype%.</li>
+          <li>has the following properties:</li>
+        </ul>
 
         <emu-clause id="sec-iterator.from">
           <h1>Iterator.from ( _O_ )</h1>