Cannot build sphinx docs without disabling sphinx.ext.pngmath extension (#52)

Author: willfurnass

docs/conf.py

@@ -54,7 +54,7 @@ def __getattr__(cls, name):
 # Add any Sphinx extension module names here, as strings. They can be extensions
 # coming with Sphinx (named 'sphinx.ext.*') or your custom ones.
 extensions = ['sphinx.ext.autodoc', 'sphinx.ext.todo', 'sphinx.ext.coverage',
-              'sphinx.ext.pngmath', 'sphinx.ext.mathjax', 'sphinx.ext.viewcode']
+              'sphinx.ext.mathjax', 'sphinx.ext.viewcode']
 
 # Add any paths that contain templates here, relative to this directory.
 templates_path = ['_templates']