Update home-page in setup.cfg

What is the problem?
The old home-page linked to http://www.openstack.org/, i think
it is not very proper. Home-page usually linked to the doc page, as
trove-dashboard does not have doc page, so i think it is proper to
change home-page to tove's doc page.

What is the solution to the problem?
Change home-page to http://docs.openstack.org/developer/trove/

Change-Id: I708a1f3ab0d131088c0197e1ef8c6cde76481125

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/trove/
 classifier =
     Environment :: OpenStack
     Intended Audience :: Information Technology