test reqs: Update pytest-rerunfailures to 2.0.1

- Prepare CLI options to pytest 3.0, to avoid a deprecation warning.
- Fix error due to missing CHANGES.rst when creating the source
  distribution by adding a MANIFEST.in.

misc/requirements/requirements-tests.txt

@@ -24,7 +24,7 @@ pytest-instafail==0.3.0
 pytest-mock==1.2
 pytest-qt==2.0.0
 pytest-repeat==0.4.0
-pytest-rerunfailures==2.0.0
+pytest-rerunfailures==2.0.1
 pytest-travis-fold==1.2.0
 pytest-warnings==0.1.0
 pytest-xvfb==0.2.1