Update rtd_requirements.txt

oesteban · effigies · web-flow · commit 772d0c86d1bd · 2019-07-17T11:50:00.000-07:00
Co-Authored-By: Chris Markiewicz &lt;effigies@gmail.com&gt;
diff --git a/rtd_requirements.txt b/rtd_requirements.txt
@@ -9,6 +9,7 @@ numpy>=1.9.0
 numpydoc
 packaging
 prov>=1.5.2
+neurdflib
 psutil
 pydot>=1.2.3
 pydotplus
