Fix local path insertion of package, fix more docs

Add back git installation docs, we'll discuss this separately.

docs/conf.py

@@ -4,7 +4,8 @@ import sys
 import os
 import re
 
-sys.path.insert(0, os.path.abspath('..'))
+if not 'READTHEDOCS' in os.environ:
+    sys.path.insert(0, os.path.abspath('..'))
 sys.path.append(os.path.abspath('./demo/'))
 
 from sphinx.locale import _

docs/contributing.rst

@@ -44,7 +44,7 @@ Making changes
 
 Changes to the theme can be compiled and tested with the default Grunt task:
 
-.. code::
+.. code:: console
 
     grunt
 

docs/installing.rst

@@ -27,3 +27,15 @@ In your ``conf.py`` file:
     strings in your translated output. If these strings are not translated in
     your output, either we lack the localized strings for your locale, or you
     are using an old version of the theme.
+
+Via Git or Download
+===================
+
+Symlink or subtree the ``sphinx_rtd_theme/sphinx_rtd_theme`` repository into your documentation at
+``docs/_themes/sphinx_rtd_theme`` then add the following two settings to your Sphinx
+``conf.py`` file:
+
+.. code:: python
+
+    html_theme = "sphinx_rtd_theme"
+    html_theme_path = ["_themes", ]

setup.py

@@ -35,7 +35,7 @@ setup(
         ]
     },
     install_requires=[
-       'sphinx'
+       'sphinx<2.0'
     ],
     extras_require={
         'dev': [