put readme test at the end

Author: nschloe

.travis.yml

@@ -32,7 +32,9 @@ addons:
 
 before_install:
   - pip install pytest pytest-cov code_extract
-  - code_extract README.md test/readme_test.py --filter python,test
+  # Make sure to put the readme test at the very end; otherwise it's messing
+  # around with the other tests.
+  - code_extract README.md test/zzz_readme_test.py --filter python,test
 
 install:
   - pip install -r test_requirements.txt