This requires Sphinx v1.7 or greater, as well as some add-ons, which can
be installed with:

pip install sphinx
pip install sphinxcontrib-programoutput
pip install git+https://github.com/esmci/sphinx_rtd_theme.git@version-dropdown-with-fixes

Check the sphinx version as follows:

>sphinx-build --version

The documentation source is stored with the CIME master code base. However, 
the built html files are stored separately in the orphan gh-pages branch
and can be viewed from a browser at URL:

http://esmci.github.io/cime

Details for working with the documentation are contained in the following
wiki page:

https://github.com/ESMCI/cime/wiki/Working-with-Sphinx-and-reStructuredText

Use the following commands to auto-build the html documentation from the main
cime/doc directory:

make clean
make api
make html

To publish the docs to the orphan gh-pages branch, follow the steps in
https://github.com/ESMCI/cime/wiki/Working-with-Sphinx-and-reStructuredText
to ensure proper versioning of the documentation.