Update the rst file information

* Update the horizon URL to the new one after doc migration
* Use https instead http
* Adjust title marker length to match the title length

Change-Id: I9c2280793bd8d6496224e36dffd479e1f3732db0
diff --git a/README.rst b/README.rst
index 126027c..fbc7156 100644
--- a/README.rst
+++ b/README.rst
@@ -2,21 +2,22 @@
 Team and repository tags
 ========================
 
-.. image:: http://governance.openstack.org/badges/tempest-horizon.svg
-    :target: http://governance.openstack.org/reference/tags/index.html
+.. image:: https://governance.openstack.org/badges/tempest-horizon.svg
+    :target: https://governance.openstack.org/reference/tags/index.html
 
 .. Change things from this point on
 
-===============================
+===============
 tempest-horizon
-===============================
+===============
 
 Tempest Plugin for Horizon tests
 
 * Free software: Apache license
 
 Using
---------
+-----
+
 Install this plugin in the same python environment as tempest.
 
 In tempest directory, run::