Call controller methods directly in test_console_output

In API unit testing, making call through WSGI is little bit overhead,
wherever applicable, unit tests can make direct call to controller
methods.

Some unit tests needs WSGI call to tests more than one plugin together.

This patch makes above cleanup in test_console_output.

Partially implements blueprint v2-on-v3-api

Change-Id: I6e915da3e8847065dab227bf8c961f690a6db98a
Merge "Call controller methods directly in test_console_output"