Reorder setup and cleanup functions for readability

As suggested on another patch, reordering these to have the setup
functions together for readability.

Partially-implements bp:resource-cleanup

Change-Id: I8e75d29edc62d30c2ba51f01a3bec490c88adde4
Add IdentityV3Client for cleanup

In identity v3 clients, there is a lot of duplicated code for
setting CONF. This patch adds IdentityV3Client for removing them.

Change-Id: Ib09342d7d831e8ac496efa0d799cd17af3c4a95f
Merge "Reorder setup and cleanup functions for readability"
Merge branch 'master' of https://github.com/openstack/tempest