Repair coverage report tox job

Coverage report job for watcher dashboard must have been
broken for an extensive amount of time. This patch
fixes it.

Change-Id: I3f0ec731d28d0f55c4378038237dc91b5c548ed5

.gitignore

@@ -24,6 +24,7 @@ pip-log.txt
 
 # Unit test / coverage reports
 .coverage
+cover/
 .tox
 nosetests.xml
 .testrepository

tox.ini

@@ -36,7 +36,14 @@ commands = {posargs}
 commands = sphinx-build -a -E -W -d releasenotes/build/doctrees --keep-going -b html releasenotes/source releasenotes/build/html
 
 [testenv:cover]
-commands = python setup.py testr --coverage --testr-args='{posargs}'
+commands =
+    coverage erase
+    coverage run --source watcher_dashboard {toxinidir}/manage.py test \
+        --settings=watcher_dashboard.test.settings \
+        --exclude-tag integration watcher_dashboard {posargs}
+    coverage xml
+    coverage html -d ./cover --omit='*tests*'
+    coverage report
 
 [testenv:docs]
 deps =