Add API and tenant var to endpoints
Add API and tenant var to endpoints

When registering the endpoints with Keystone it looks like a
Trove API version and tenant var should be included in the endpoint
string

I'm not creating a pull request for this as the endpoint format is
based on old Icehouse documentation *1 and I'm not sure what Trove
API version the charm supports

*1 http://docs.openstack.org/icehouse/install-guide/install/apt/content/trove-install.html

TransCirrus/charm-trove