Rename requires files to standard names.

    Rename tools/pip-requires to requirements.txt and tools/test-requires
    to test-requirements.txt. These are standard files, and tools in the
    general world are growing intelligence about them.

    adding test-requirements.txt to quantumclient/openstack/common/setup.py per review instructions.

Change-Id: Ibf991b400bfbeb4222216649901586e01a0255b1
Fixes: bug #1179008
Merge "   Rename requires files to standard names."