docs: fix syntax highlighting of code blocks

And various other cleanups

Change-Id: If945f5407036e73db980cafd2185359a488a0ff1
diff --git a/docs/conf.py b/docs/conf.py
index d3b203a..cd2092d 100644
--- a/docs/conf.py
+++ b/docs/conf.py
@@ -23,10 +23,10 @@
 copyright = u'Copyright © 2013-2020 Regents of the University of California.'
 author = u'Named Data Networking Project'
 
-# The short X.Y version
+# The short X.Y version.
 #version = ''
 
-# The full version, including alpha/beta/rc tags
+# The full version, including alpha/beta/rc tags.
 #release = ''
 
 # There are two options for replacing |today|: either, you set today to some
@@ -40,7 +40,7 @@
 
 # If your documentation needs a minimal Sphinx version, state it here.
 #
-needs_sphinx = '1.1'
+needs_sphinx = '1.3'
 
 # Add any Sphinx extension module names here, as strings. They can be
 # extensions coming with Sphinx (named 'sphinx.ext.*') or your custom
@@ -87,6 +87,9 @@
 # so a file named "default.css" will overwrite the builtin "default.css".
 html_static_path = ['_static']
 
+# Disable syntax highlighting of code blocks by default.
+highlight_language = 'none'
+
 
 # -- Options for LaTeX output ------------------------------------------------