Fix broken coverage reporting

.travis.yml

@@ -28,7 +28,7 @@ install:
   - "pip install ."
 # command to run tests, e.g. python setup.py test
 script:
-  python setup.py develop && coverage run --source=pwman setup.py test
+  python setup.py develop && coverage run -m tests.test_pwman
 
 after_success:
   coveralls

Makefile

@@ -51,7 +51,7 @@ test-all:
 	tox
 
 coverage-run:
-	coverage run --source pwman setup.py test
+	coverage run -m tests.test_pwman
 	coverage report -m
 	@coverage html