Update page 'Home'

Home.md

@@ -55,3 +55,11 @@ To start the app, you just have to run `calsocial` as a module:
     pipenv run env flask run
     
 After this, your local instance is available on http://127.0.0.1:5000/
+
+## Run the tests
+
+To run tests, use `pytest` (`PYTHONPATH` needs to be set explicitly, as `pipenv` doesn’t do it by default):
+
+    pipenv run env PYTHONPATH=$(pwd) pytest --cov=calsocial
+    
+This will also print a nice coverage report at the end.