Added link to the trove developer docs in the openstack-projects page

Added a link to the generated trove developer docs
(http://docs.openstack.org/developer/trove/) in the openstack-projects
page.

Change-Id: If84b4c27c6627cdccb6919ed711a2e1b97475c82
Merge "Added link to the trove developer docs in the openstack-projects page"