Release v1.6.0 (#324)

* Update version and changelog for v1.6.0
* Update docs
diff --git a/docs/epy/googleapiclient-module.html b/docs/epy/googleapiclient-module.html
index 79098cd..160590c 100644
--- a/docs/epy/googleapiclient-module.html
+++ b/docs/epy/googleapiclient-module.html
@@ -57,7 +57,7 @@
 <h1 class="epydoc">Package googleapiclient</h1><p class="nomargin-top"><span class="codelink"><a href="googleapiclient-pysrc.html">source&nbsp;code</a></span></p>
 <hr />
 <div class="fields">      <p><strong>Version:</strong>
-        1.5.5
+        1.6.0
       </p>
 </div><!-- ==================== SUBMODULES ==================== -->
 <a name="section-Submodules"></a>
@@ -78,6 +78,7 @@
 </tr>
   <tr><td class="summary">
   <ul class="nomargin">
+    <li class="private"> <strong class="uidlink"><a href="googleapiclient._auth-module.html">googleapiclient._auth</a></strong>: <em class="summary">Helpers for authentication using oauth2client or google-auth.</em>    </li>
     <li> <strong class="uidlink"><a href="googleapiclient.channel-module.html">googleapiclient.channel</a></strong>: <em class="summary">Channel notifications support.</em>    </li>
     <li> <strong class="uidlink"><a href="googleapiclient.discovery-module.html">googleapiclient.discovery</a></strong>: <em class="summary">Client for discovery based APIs.</em>    </li>
     <li> <strong class="uidlink"><a href="googleapiclient.discovery_cache-module.html">googleapiclient.discovery_cache</a></strong>: <em class="summary">Caching utility for the discovery document.</em>
@@ -148,7 +149,7 @@
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     <td align="left" class="footer">
-    Generated by Epydoc 3.0.1 on Tue Nov  1 17:02:49 2016
+    Generated by Epydoc 3.0.1 on Thu Jan  5 12:55:02 2017
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