Fix contact/enroll confirmation being hidden along with the form it lived inside

Both forms nested their status message as a child of the <form>, so
form.hidden = true on success hid the confirmation right along with it —
looked like nothing happened. Contact form now resets and stays usable
(you can send another message) instead of disappearing; enroll form still
hides after signup (no reason to sign up twice), but its confirmation is
now a sibling so it actually stays visible.

Also generalized the privacy policy's language from being anchored on
email courses specifically to covering any use of the site.

layouts/courses/single.html

@@ -13,8 +13,8 @@
   </div>
 
   <button type="submit" class="btn">Send me day one</button>
-  <p id="enroll-status" role="status" style="margin-top:1rem;"></p>
 </form>
+<p id="enroll-status" role="status" style="margin-top:1rem;"></p>
 
 <script>
   (function () {