Try to build HTML5 for docs.

docs/conf.py

@@ -128,6 +128,8 @@ pygments_style = 'friendly'
 
 # -- Options for HTML output ----------------------------------------------
 
+html_experimental_html5_writer = True
+
 # The theme to use for HTML and HTML Help pages.  See the documentation for
 # a list of builtin themes.
 html_theme = 'basic'

setup.py

@@ -10,6 +10,7 @@ with open('requirements.txt') as f:
 if on_rtd:
   requirements.append('sphinxcontrib-napoleon')
   requirements.append('sphinxcontrib-asyncio')
+  requirements.append('sphinx==1.6.3')
 
 version = ''
 with open('discord/__init__.py') as f: