Make identity v3 services_client 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 identity v3 services_client list API accept
filter param.

Also add and correct doc string link.

Partially implements blueprint consistent-service-method-names

Change-Id: Iac174a5d6ab650c4512d0961d10f83a9c23eee52
1 file changed