Improving cover testenv

- Add coverage report to analyze code.

Change-Id: Ie321de50872d8e21bf69e913a0e5db6e0cccdcb3

tox.ini

@@ -11,16 +11,20 @@ setenv =
 deps = -r{toxinidir}/test-requirements.txt
 commands = python setup.py test --slowest --testr-args='{posargs}'
 whitelist_externals = sh
+                      find
 
 [testenv:pep8]
 commands = sh tools/pretty_flake8.sh
 
-
 [testenv:venv]
 commands = {posargs}
 
 [testenv:cover]
-commands = python setup.py test --coverage --testr-args='{posargs}'
+commands = 
+  coverage erase
+  find . -type f -name "*.pyc" -delete
+  python setup.py testr --coverage --testr-args='{posargs}'
+  coverage report
 
 [testenv:docs]
 commands = python setup.py build_sphinx