Make volume backups_client to use **kwargs

As we discussed on
http://lists.openstack.org/pipermail/openstack-dev/2015-July/068864.html
All http POST/PUT methods need to contain **kwargs as their arguments.

This patch makes volume backups_client use **kwargs.

Partially implements blueprint consistent-service-method-names

Change-Id: I8f284a5018f03a8dcd706398fec8562d2d1c11e5
2 files changed