Handle tutorial walkthrough

webadmin/src/index.html

@@ -64,6 +64,7 @@
             <h2>Welcome</h2>
             <p>This page is the configuration interface to your Cloudron.</p>
             <br/>
+            <button class="btn btn-default pull-left" ng-click="endTutorial();">Skip</button>
             <button class="btn btn-success pull-right" ng-click="nextWelcomeStep();">Next</button>
         </div>