Update policy.md

Adding deadline to comment period.

Author: Bill Hunt

pages/policy.md

@@ -20,6 +20,9 @@ sidenav: policy
   <p>
     3. Send your content suggestions or proposed revisions to the OMB Office of the Federal Chief Information Officer via email to <a href="mailto:{{site.mail}}">{{site.mail}}</a>. Please note that all comments received will be posted publicly.
   </p>
+  <p>
+    Comments must be received on or before December 26, 2018.
+  </p>
 </header>
 {% endif %}