Add delete role operation in Identity API v3 ref
Add delete role operation in Identity API v3 ref

1. Add DELETE "/v3/roles/{role_id}" in Roles section.

Change-Id: Ic211c01825eef477d312858bb6bf04f4873603d1
Closes-Bug: #1466868

dreamhost/api-site,openstack/api-site,Tesora/tesora-api-site,Tesora/tesora-api-site,openstack/api-site,dreamhost/api-site,dreamhost/api-site,dreamhost/api-site,Tesora/tesora-api-site,Tesora/tesora-api-site,dreamhost/api-site,openstack/api-site,dreamhost/api-site,openstack/api-site,Tesora/tesora-api-site,dreamhost/api-site,Tesora/tesora-api-site,Tesora/tesora-api-site