Add OpenStack Databases (trove) API to api-site

Removed XML request and response examples
because they are no longer supported

Closes-Bug: #1303966

Change-Id: Ice6ee57d22ffb75fbf2e30d2105ff7fb64e7a7cf
author: diane fleming
Better page title

Also more consistent with other *.openstack.org pages.

Change-Id: I6660a9042d56c176885bdbc679b67df58cf317af
Implements: blueprint developer-openstack-org
Merge "Better page title"
Merge "Add OpenStack Databases (trove) API to api-site"