Update RTD url

They now use .io rather than .org. Also, default to HTTPS

Author: jeffwidman

setup.cfg

@@ -20,7 +20,7 @@ classifier =
     Environment :: Console
 keywords =
     virtualenv
-home-page = http://virtualenvwrapper.readthedocs.org/
+home-page = https://virtualenvwrapper.readthedocs.io/
 zip_safe = False
 
 [files]