Fix issue with doc generation, missing theme

doc/conf.py

@@ -19,6 +19,7 @@
 import sys
 import os
 import shlex
+import sphinx_rtd_theme
 
 # If extensions (or modules to document with autodoc) are in another directory,
 # add these directories to sys.path here. If the directory is relative to the
@@ -123,7 +124,7 @@ html_theme = 'sphinx_rtd_theme'
 #html_theme_options = {}
 
 # Add any paths that contain custom themes here, relative to this directory.
-#html_theme_path = []
+html_theme_path = [sphinx_rtd_theme.get_html_theme_path()]
 
 # The name for this set of Sphinx documents.  If None, it defaults to
 # "<project> v<release> documentation".