Verify list_addresses_by_network APIs attributes

This patch adds the JSON schema for Nova V2 & V3 server
list_addresses_by_network APIs response and validate the
response with added JSON schema to block the backward
incompatibility change in the future.

The response body of server list_addresses_by_network V2 API is below:

{
    "private": [
        {
            "version": 4,
            "addr": "192.168.0.3"
        }
    ]
}

The response body of server list_addresses_by_network V3 API is below:

{
    "private": [
        {
            "version": 4,
            "addr": "192.168.0.3",
            "type": "fixed",
            "mac_addr": "aa:bb:cc:dd:ee:ff"
        }
    ]
}

Partially implements blueprint nova-api-attribute-test

Change-Id: I76e25523708fb9454518f215dc60f201d7483464
Remove tempest_auto_config script

This script isn't being used by anyone to my knowledge nor has it
really been maintained since it was first added. We will be working
on a plan for automating tempest configuration soon and this
doesn't really fit the initial set requirements of requirements. It
also does not have any testing, so I expect that it has bit rotted
and probably doesn't work anymore.

Change-Id: Id896d9877312dfb6b12b54ea1c598a1940cdd9ce
Get credential IDs from Credentials class

With the move to Credentials class, tenant_id and user_id are
available in the Credentials instance.
Several test use identity admin client to obtain tenant_id
and user_id, fixing them to get the IDs from Credentials instead.

Partially implements: bp multi-keystone-api-version-tests

Change-Id: I8c38fb8d191a88fab37633c6edffd54492c41fd5
Merge "Verify list_addresses_by_network APIs attributes"
Merge "Remove tempest_auto_config script"
Merge "Get credential IDs from Credentials class"