Regen all docs. (#700)

* Stop recursing if discovery == {}

* Generate docs with 'make docs'.
diff --git a/docs/dyn/classroom_v1.html b/docs/dyn/classroom_v1.html
index ad3ec83..cb260f5 100644
--- a/docs/dyn/classroom_v1.html
+++ b/docs/dyn/classroom_v1.html
@@ -85,6 +85,11 @@
 <p class="firstline">Returns the invitations Resource.</p>
 
 <p class="toc_element">
+  <code><a href="classroom_v1.registrations.html">registrations()</a></code>
+</p>
+<p class="firstline">Returns the registrations Resource.</p>
+
+<p class="toc_element">
   <code><a href="classroom_v1.userProfiles.html">userProfiles()</a></code>
 </p>
 <p class="firstline">Returns the userProfiles Resource.</p>