adding dependencies required for building the html doc to README.txt
The docs for this project are built with Sphinx. To compile the docs, first ensure that Sphinx and the ReadTheDocs theme are installed.
```
-conda install sphinx sphinx_rtd_theme
+conda install sphinx sphinx_rtd_theme nbsphinx
+pip install sphinx_automodapi
```
Once installed, you can use the Makefile in this directory to compile static HTML pages by
