Merge pull request #245 from fantix/pyup-update-sphinx-rtd-theme-0.3.1-to-0.4.0

Update sphinx-rtd-theme to 0.4.0

Author: wwwjfy

requirements_dev.txt

@@ -28,4 +28,4 @@ pytest-cov==2.5.1
 Sphinx==1.7.5
 Pygments==2.2.0
 sphinxcontrib-asyncio==0.2.0
-sphinx-rtd-theme==0.3.1
+sphinx-rtd-theme==0.4.0