Fix order of arguments in assertEqual

Some tests used incorrect order assertEqual(observed, expected).

The correct order expected by testtools is
assertEqual(expected, observed).

Change-Id: I87f90b9fefbf39e92446d7724e7b8e457e114716
Partial-Bug: #1259292
Make v2.1 tests use wsgi_app_v21 and remove wsgi_app_v3

Nova v3 API has disappeared but some tests still access v3 URLs.
This patch makes them use wsgi_app_v21 and access to v2.1 URLs.
In addition, this patch removes wsgi_app_v3 because it is not
used after this change.

Partially implements blueprint v2-on-v3-api

Change-Id: Ic36d86dce8a35933c15ec820b273825bb0353864
Add API validation schema for floating_ip_dns

This patch adds validation json schema for the floating_ip_dns api.

Partially implements blueprint v2-on-v3-api

Change-Id: Iefb6a4503781fcc349cf5101d4ce10cc3422f52b
Fix the unittest use wrong controller for SecurityGroups V2

V2.1 and V2 API are sharing some set of unittest. But the unittest
for SecurityGroups V2 use the wrong controller. This patch fixes this.

Change-Id: I03cc6f3e4c1985fd961378d819c032f7a7c3d8ba
Merge "Fix order of arguments in assertEqual"
Merge "Fix the unittest use wrong controller for SecurityGroups V2"
Merge "Make v2.1 tests use wsgi_app_v21 and remove wsgi_app_v3"
Merge "Add API validation schema for floating_ip_dns"