Use 'make check' instead of 'python3 tools/rstlint.py' (python#96)

Author: berkerpeksag

.travis.yml

@@ -37,7 +37,7 @@ matrix:
         - pip install -U Sphinx
       script:
         - make html SPHINXOPTS="-q"
-        - python tools/rstlint.py -i tools -i venv
+        - make check
     - os: linux
       language: cpp
       compiler: clang