Add "volume transfer request delete" command in
volume v1 and v2. Also add the unit tests, docs,
release note and functional tests
Change-Id: Ic3d375bc8df3312fac53c1800d75f48376b8c91c
Implements: bp cinder-command-support
Co-Authored-By: Sheel Rana <ranasheel2000@gmail.com>