quantum-debug command should use QUANTUM_ prefixed environment variables

[Nachi Ueno]

TEST_CONFIG_FILE, which is used by quantum-debug command, should be QUNATUM_TEST_CONFIG_FILE because
TEST_CINFIG_FILE is too generic.

This bug based on the review of
In the review comment of quantum-gating,
https://review.openstack.org/#/c/14990/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/15780

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/15780
Committed: http://github.com/openstack/quantum/commit/12674de39673975ec9a9bf9eaee3bd7956bf9bcb
Submitter: Jenkins
Branch: master

commit 12674de39673975ec9a9bf9eaee3bd7956bf9bcb
Author: Nachi Ueno <email address hidden>
Date: Fri Nov 9 13:36:44 2012 -0800

    Add QUANTUM_ prefix for env used by quantum-debug

    Fixes bug 1077204
    from TEST_CONFIG_FILE to QUANTUM_TEST_CONFIG_FILE
    also fixes openstack-common style

    Change-Id: I03d386dd5fc28d91ef496aecb1b93ddb4f4a810d