Fix Kolla home-page URL

The link http://docs.openstack.org/developer/openstack-projects.html
contains project-specific documentation for OpenStack services and
libraries.
And here you will see kolla home-page url as follow:
http://docs.openstack.org/developer/kolla/

TrivialFix.

Change-Id: I77d822f3f7211d02d58529128f9b37d6096ca32a

setup.cfg

@@ -5,7 +5,7 @@ description-file =
     README.rst
 author = OpenStack
 author-email = openstack-dev@lists.openstack.org
-home-page = http://www.openstack.org/
+home-page = http://docs.openstack.org/developer/kolla/
 classifier =
     Environment :: OpenStack
     Intended Audience :: Information Technology