Update run_tests and bring back colorizer.

This patch adds output of tests and their results to run_tests.sh.
It also brings back colorizer to the output and updates the test-requirements.

Should align with cinder changes that are in progress
at: https://review.openstack.org/#/c/30291/

Change-Id: I3df6d861f4b4d4355464ceb2d507e69bcf682fbe
Merge "Update run_tests and bring back colorizer."